mirror of
https://github.com/MariaDB/server.git
synced 2025-01-31 02:51:44 +01:00
5569b3eb09
InnoDB takes a lot of time to perform null updates. The reason is that
even though an empty update vector was created, InnoDB will go on to
write undo log records and update the system columns
DB_TRX_ID and DB_ROLL_PTR in the clustered index, and of course write
redo log for all this.
This could have been fixed properly in
commit 54a492ecac more than 10 years ago.
1417 lines
29 KiB
Text
1417 lines
29 KiB
Text
#
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# WL#6742 - Test the interaction of multiple transactions using
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# different isolation levels to make sure that the value returned
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# by count(*) always reflects the correct view of the table according
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# to the transaction's selected isolation level.
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#
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#
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# Traverse various indexes to get the right counts.
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# This especially tests count(*) which is pushed down to InnoDB in WL#6742.
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#
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CREATE TABLE t1 (
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c1 INT AUTO_INCREMENT PRIMARY KEY,
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c2 INT,
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c3 INT,
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c4 INT,
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INDEX k2(c2)
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) Engine=InnoDB;
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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INSERT INTO t1(c2,c3,c4) VALUES (1, 1, 1);
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CREATE TABLE t2 LIKE t1;
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INSERT INTO t2 (SELECT * FROM t1);
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affected rows: 10
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info: Records: 10 Duplicates: 0 Warnings: 0
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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1 1 1 1
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2 1 1 1
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3 1 1 1
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4 1 1 1
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5 1 1 1
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6 1 1 1
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7 1 1 1
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8 1 1 1
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9 1 1 1
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10 1 1 1
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SELECT COUNT(*) FROM t1;
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COUNT(*)
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10
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SELECT COUNT(c1) FROM t1;
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COUNT(c1)
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10
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SELECT COUNT(c2) FROM t1;
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COUNT(c2)
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10
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SELECT COUNT(c3) FROM t1;
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COUNT(c3)
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10
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SELECT SUM(c1) FROM t1;
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SUM(c1)
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55
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SELECT SUM(c2) FROM t1;
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SUM(c2)
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10
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SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
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5.5000 10 1 1.0000 10
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SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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c1 c2
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6 1
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7 1
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8 1
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9 1
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10 1
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SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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COUNT(c2)
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5
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SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
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COUNT(*)
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5
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###############################################
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#
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# Do some DML in the default connection and leave the transaction pending.
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#
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SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
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BEGIN;
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UPDATE t1 SET c2 = c2 * 3 WHERE c1 = 1;
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affected rows: 1
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info: Rows matched: 1 Changed: 1 Warnings: 0
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DELETE FROM t1 WHERE c1 = 6;
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affected rows: 1
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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1 3 1 1
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2 1 1 1
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3 1 1 1
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4 1 1 1
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5 1 1 1
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7 1 1 1
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8 1 1 1
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9 1 1 1
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10 1 1 1
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SELECT COUNT(*) FROM t1;
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COUNT(*)
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9
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SELECT COUNT(c1) FROM t1;
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COUNT(c1)
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9
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SELECT COUNT(c2) FROM t1;
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COUNT(c2)
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9
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SELECT COUNT(c3) FROM t1;
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COUNT(c3)
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9
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SELECT SUM(c1) FROM t1;
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SUM(c1)
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49
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SELECT SUM(c2) FROM t1;
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SUM(c2)
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11
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SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
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5.4444 10 1 1.0000 9
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SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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c1 c2
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5 1
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7 1
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8 1
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9 1
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10 1
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SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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COUNT(c2)
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5
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SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
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COUNT(*)
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4
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###############################################
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#
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# Start transactions of Repeatable Read, Read Committed, and Read Uncommitted
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#
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# Connection 1 REPEATABLE READ
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#
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connect con1,localhost,root,,;
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SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
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BEGIN;
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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1 1 1 1
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2 1 1 1
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3 1 1 1
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4 1 1 1
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5 1 1 1
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6 1 1 1
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7 1 1 1
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8 1 1 1
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9 1 1 1
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10 1 1 1
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SELECT COUNT(*) FROM t1;
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COUNT(*)
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10
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SELECT COUNT(c1) FROM t1;
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COUNT(c1)
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10
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SELECT COUNT(c2) FROM t1;
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COUNT(c2)
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10
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SELECT COUNT(c3) FROM t1;
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COUNT(c3)
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10
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SELECT SUM(c1) FROM t1;
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SUM(c1)
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55
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SELECT SUM(c2) FROM t1;
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SUM(c2)
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10
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SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
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5.5000 10 1 1.0000 10
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SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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c1 c2
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6 1
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7 1
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8 1
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9 1
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10 1
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SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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COUNT(c2)
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5
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SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
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COUNT(*)
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5
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###############################################
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UPDATE t1 SET c2 = c2 * 5 WHERE c1 = 2;
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affected rows: 1
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info: Rows matched: 1 Changed: 1 Warnings: 0
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DELETE FROM t1 WHERE c1 = 7;
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affected rows: 1
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INSERT INTO t1(c2,c3,c4) VALUES (100, 1, 1);
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affected rows: 1
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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1 1 1 1
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2 5 1 1
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3 1 1 1
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4 1 1 1
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5 1 1 1
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6 1 1 1
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8 1 1 1
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9 1 1 1
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10 1 1 1
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11 100 1 1
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SELECT COUNT(*) FROM t1;
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COUNT(*)
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10
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SELECT COUNT(c1) FROM t1;
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COUNT(c1)
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10
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SELECT COUNT(c2) FROM t1;
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COUNT(c2)
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10
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SELECT COUNT(c3) FROM t1;
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COUNT(c3)
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10
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SELECT SUM(c1) FROM t1;
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SUM(c1)
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59
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SELECT SUM(c2) FROM t1;
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SUM(c2)
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113
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SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
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5.9000 11 1 1.0000 10
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SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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c1 c2
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6 1
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8 1
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9 1
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10 1
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11 100
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SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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COUNT(c2)
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5
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SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
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COUNT(*)
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5
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###############################################
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#
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# Test a lock wait timeout during COUNT(*)
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#
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SET innodb_lock_wait_timeout = 1;
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SELECT COUNT(*) FROM t1 FOR UPDATE;
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ERROR HY000: Lock wait timeout exceeded; try restarting transaction
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#
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# Connection 2 READ COMMITTED
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#
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connect con2,localhost,root,,;
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SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
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BEGIN;
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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1 1 1 1
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2 1 1 1
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3 1 1 1
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4 1 1 1
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5 1 1 1
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6 1 1 1
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7 1 1 1
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8 1 1 1
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9 1 1 1
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10 1 1 1
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SELECT COUNT(*) FROM t1;
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COUNT(*)
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10
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SELECT COUNT(c1) FROM t1;
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COUNT(c1)
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10
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SELECT COUNT(c2) FROM t1;
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COUNT(c2)
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10
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SELECT COUNT(c3) FROM t1;
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COUNT(c3)
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10
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SELECT SUM(c1) FROM t1;
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SUM(c1)
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55
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SELECT SUM(c2) FROM t1;
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SUM(c2)
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10
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SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
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5.5000 10 1 1.0000 10
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SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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c1 c2
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6 1
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7 1
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8 1
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9 1
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10 1
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SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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COUNT(c2)
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5
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SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
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COUNT(*)
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5
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###############################################
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UPDATE t1 SET c2 = c2 * 7 WHERE c1 = 3;
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affected rows: 1
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info: Rows matched: 1 Changed: 1 Warnings: 0
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DELETE FROM t1 WHERE c1 = 8;
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affected rows: 1
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INSERT INTO t1(c2,c3,c4) VALUES (1000, 1, 1);
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affected rows: 1
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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1 1 1 1
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2 1 1 1
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3 7 1 1
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4 1 1 1
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|
5 1 1 1
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6 1 1 1
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7 1 1 1
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9 1 1 1
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10 1 1 1
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12 1000 1 1
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SELECT COUNT(*) FROM t1;
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COUNT(*)
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10
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SELECT COUNT(c1) FROM t1;
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COUNT(c1)
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10
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SELECT COUNT(c2) FROM t1;
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COUNT(c2)
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10
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SELECT COUNT(c3) FROM t1;
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COUNT(c3)
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10
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SELECT SUM(c1) FROM t1;
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SUM(c1)
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59
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SELECT SUM(c2) FROM t1;
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SUM(c2)
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1015
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SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
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5.9000 12 1 1.0000 10
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SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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c1 c2
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6 1
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7 1
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|
9 1
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|
10 1
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|
12 1000
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SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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COUNT(c2)
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5
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SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
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COUNT(*)
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5
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###############################################
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#
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# Connection 3 READ UNCOMMITTED
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#
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connect con3,localhost,root,,;
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SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
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BEGIN;
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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1 3 1 1
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2 5 1 1
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3 7 1 1
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4 1 1 1
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|
5 1 1 1
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9 1 1 1
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10 1 1 1
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11 100 1 1
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12 1000 1 1
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SELECT COUNT(*) FROM t1;
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COUNT(*)
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9
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SELECT COUNT(c1) FROM t1;
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COUNT(c1)
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9
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SELECT COUNT(c2) FROM t1;
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COUNT(c2)
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9
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SELECT COUNT(c3) FROM t1;
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COUNT(c3)
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9
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SELECT SUM(c1) FROM t1;
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SUM(c1)
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57
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SELECT SUM(c2) FROM t1;
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SUM(c2)
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1119
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SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
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6.3333 12 1 1.0000 9
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SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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c1 c2
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5 1
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|
9 1
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|
10 1
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|
11 100
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|
12 1000
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SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
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COUNT(c2)
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5
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SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
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COUNT(*)
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4
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###############################################
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UPDATE t1 SET c2 = c2 * 11 WHERE c1 = 4;
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affected rows: 1
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info: Rows matched: 1 Changed: 1 Warnings: 0
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INSERT INTO t1(c2,c3,c4) VALUES (10000, 1, 1);
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affected rows: 1
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DELETE FROM t1 WHERE c1 in(9);
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affected rows: 1
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########## innodb_isolation_selects.inc ##########
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SELECT * FROM t1;
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c1 c2 c3 c4
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|
1 3 1 1
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|
2 5 1 1
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|
3 7 1 1
|
|
4 11 1 1
|
|
5 1 1 1
|
|
10 1 1 1
|
|
11 100 1 1
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|
12 1000 1 1
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|
13 10000 1 1
|
|
SELECT COUNT(*) FROM t1;
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COUNT(*)
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|
9
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|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
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|
9
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
9
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|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
9
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
61
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11128
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
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AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.7778 13 1 1.0000 9
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
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|
5 1
|
|
10 1
|
|
11 100
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
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|
4
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|
###############################################
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|
#
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|
# Connection default REPEATABLE READ
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|
#
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|
connection default;
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########## innodb_isolation_selects.inc ##########
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|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 3 1 1
|
|
2 1 1 1
|
|
3 1 1 1
|
|
4 1 1 1
|
|
5 1 1 1
|
|
7 1 1 1
|
|
8 1 1 1
|
|
9 1 1 1
|
|
10 1 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
9
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
9
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
9
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
9
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
49
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
5.4444 10 1 1.0000 9
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
5 1
|
|
7 1
|
|
8 1
|
|
9 1
|
|
10 1
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
#
|
|
# Commit the 3 extra connections
|
|
#
|
|
# Connection 1 REPEATABLE READ
|
|
#
|
|
connection con1;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 1 1 1
|
|
2 5 1 1
|
|
3 1 1 1
|
|
4 1 1 1
|
|
5 1 1 1
|
|
6 1 1 1
|
|
8 1 1 1
|
|
9 1 1 1
|
|
10 1 1 1
|
|
11 100 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
10
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
10
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
10
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
10
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
59
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
113
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
5.9000 11 1 1.0000 10
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
6 1
|
|
8 1
|
|
9 1
|
|
10 1
|
|
11 100
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
5
|
|
###############################################
|
|
#
|
|
# Connection 2 READ COMMITTED
|
|
#
|
|
connection con2;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 1 1 1
|
|
2 1 1 1
|
|
3 7 1 1
|
|
4 1 1 1
|
|
5 1 1 1
|
|
6 1 1 1
|
|
7 1 1 1
|
|
9 1 1 1
|
|
10 1 1 1
|
|
12 1000 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
10
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
10
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
10
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
10
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
59
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
1015
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
5.9000 12 1 1.0000 10
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
6 1
|
|
7 1
|
|
9 1
|
|
10 1
|
|
12 1000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
5
|
|
###############################################
|
|
#
|
|
# Connection 3 READ UNCOMMITTED
|
|
#
|
|
connection con3;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 3 1 1
|
|
2 5 1 1
|
|
3 7 1 1
|
|
4 11 1 1
|
|
5 1 1 1
|
|
10 1 1 1
|
|
11 100 1 1
|
|
12 1000 1 1
|
|
13 10000 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
9
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
9
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
9
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
9
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
61
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11128
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.7778 13 1 1.0000 9
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
5 1
|
|
10 1
|
|
11 100
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
COMMIT;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 3 1 1
|
|
2 5 1 1
|
|
3 7 1 1
|
|
4 11 1 1
|
|
5 1 1 1
|
|
10 1 1 1
|
|
11 100 1 1
|
|
12 1000 1 1
|
|
13 10000 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
9
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
9
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
9
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
9
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
61
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11128
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.7778 13 1 1.0000 9
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
5 1
|
|
10 1
|
|
11 100
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
#
|
|
# Connection 2 READ COMMITTED
|
|
#
|
|
connection con2;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 1 1 1
|
|
2 1 1 1
|
|
3 7 1 1
|
|
4 11 1 1
|
|
5 1 1 1
|
|
6 1 1 1
|
|
7 1 1 1
|
|
10 1 1 1
|
|
12 1000 1 1
|
|
13 10000 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
10
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
10
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
10
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
10
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
63
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11024
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.3000 13 1 1.0000 10
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
6 1
|
|
7 1
|
|
10 1
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
COMMIT;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 1 1 1
|
|
2 1 1 1
|
|
3 7 1 1
|
|
4 11 1 1
|
|
5 1 1 1
|
|
6 1 1 1
|
|
7 1 1 1
|
|
10 1 1 1
|
|
12 1000 1 1
|
|
13 10000 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
10
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
10
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
10
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
10
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
63
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11024
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.3000 13 1 1.0000 10
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
6 1
|
|
7 1
|
|
10 1
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
#
|
|
# Connection 1 REPEATABLE READ
|
|
#
|
|
connection con1;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 1 1 1
|
|
2 5 1 1
|
|
3 1 1 1
|
|
4 1 1 1
|
|
5 1 1 1
|
|
6 1 1 1
|
|
8 1 1 1
|
|
9 1 1 1
|
|
10 1 1 1
|
|
11 100 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
10
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
10
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
10
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
10
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
59
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
113
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
5.9000 11 1 1.0000 10
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
6 1
|
|
8 1
|
|
9 1
|
|
10 1
|
|
11 100
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
5
|
|
###############################################
|
|
#
|
|
# Select the first 5 records FOR UPDATE using count(*) in a subquery.
|
|
# The second record is still pending so we get a lock timeout.
|
|
#
|
|
SET innodb_lock_wait_timeout = 1;
|
|
SELECT c1, c2 FROM t1 WHERE c1 < ((SELECT COUNT(*) FROM t1) / 2) FOR UPDATE;
|
|
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
|
|
SELECT COUNT(*) FROM t1 FOR UPDATE;
|
|
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
|
|
COMMIT;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 1 1 1
|
|
2 5 1 1
|
|
3 7 1 1
|
|
4 11 1 1
|
|
5 1 1 1
|
|
6 1 1 1
|
|
10 1 1 1
|
|
11 100 1 1
|
|
12 1000 1 1
|
|
13 10000 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
10
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
10
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
10
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
10
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
67
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11127
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.7000 13 1 1.0000 10
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
6 1
|
|
10 1
|
|
11 100
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
#
|
|
# Show The EXPLAIN output for these queries;
|
|
#
|
|
EXPLAIN SELECT * FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 12 #
|
|
EXPLAIN SELECT COUNT(*) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL k2 5 NULL 12 Using index
|
|
EXPLAIN SELECT COUNT(c1) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL k2 5 NULL 12 Using index
|
|
EXPLAIN SELECT COUNT(c2) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL k2 5 NULL 12 #
|
|
EXPLAIN SELECT COUNT(c3) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 12 #
|
|
EXPLAIN SELECT SUM(c1) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL k2 5 NULL 12 #
|
|
EXPLAIN SELECT SUM(c2) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL k2 5 NULL 12 #
|
|
EXPLAIN SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 12 #
|
|
EXPLAIN SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 range PRIMARY PRIMARY 4 NULL 8 #
|
|
2 SUBQUERY t1 index NULL k2 5 NULL 12 #
|
|
EXPLAIN SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 range PRIMARY PRIMARY 4 NULL 8 #
|
|
2 SUBQUERY t1 index NULL k2 5 NULL 12 #
|
|
EXPLAIN SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 range PRIMARY PRIMARY 4 NULL 7 #
|
|
2 SUBQUERY t1 index NULL k2 5 NULL 12 #
|
|
#
|
|
# Make all indexes in t2 obsolete to the active repeatable read transaction
|
|
# in the default connection.
|
|
#
|
|
ALTER TABLE t2 row_format=redundant;
|
|
#
|
|
# Connection default REPEATABLE READ
|
|
# Do more DML in the default REPEATABLE READ transaction in order to use recently committed records.
|
|
#
|
|
connection default;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 3 1 1
|
|
2 1 1 1
|
|
3 1 1 1
|
|
4 1 1 1
|
|
5 1 1 1
|
|
7 1 1 1
|
|
8 1 1 1
|
|
9 1 1 1
|
|
10 1 1 1
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
9
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
9
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
9
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
9
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
49
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
5.4444 10 1 1.0000 9
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
5 1
|
|
7 1
|
|
8 1
|
|
9 1
|
|
10 1
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
UPDATE t1 SET c4 = c2 * 10;
|
|
affected rows: 9
|
|
info: Rows matched: 9 Changed: 9 Warnings: 0
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 3 1 30
|
|
2 5 1 50
|
|
3 7 1 70
|
|
4 11 1 110
|
|
5 1 1 10
|
|
7 1 1 1
|
|
8 1 1 1
|
|
9 1 1 1
|
|
10 1 1 10
|
|
11 100 1 1000
|
|
12 1000 1 10000
|
|
13 10000 1 100000
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
12
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
12
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
12
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
12
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
85
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11131
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
7.0833 13 1 1.0000 111283
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
7 1
|
|
8 1
|
|
9 1
|
|
10 1
|
|
11 100
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
7
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
6
|
|
###############################################
|
|
#
|
|
# Table t2 has been altered to a new row format.
|
|
# The index should not be useable.
|
|
#
|
|
SELECT COUNT(*) FROM t2;
|
|
ERROR HY000: Table definition has changed, please retry transaction
|
|
SELECT * FROM t2;
|
|
ERROR HY000: Table definition has changed, please retry transaction
|
|
COMMIT;
|
|
SELECT COUNT(*) FROM t2;
|
|
COUNT(*)
|
|
10
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 3 1 30
|
|
2 5 1 50
|
|
3 7 1 70
|
|
4 11 1 110
|
|
5 1 1 10
|
|
10 1 1 10
|
|
11 100 1 1000
|
|
12 1000 1 10000
|
|
13 10000 1 100000
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
9
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
9
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
9
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
9
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
61
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11128
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.7778 13 1 1.0000 111280
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
5 1
|
|
10 1
|
|
11 100
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
#
|
|
# Connection 2
|
|
#
|
|
connection con2;
|
|
########## innodb_isolation_selects.inc ##########
|
|
SELECT * FROM t1;
|
|
c1 c2 c3 c4
|
|
1 3 1 30
|
|
2 5 1 50
|
|
3 7 1 70
|
|
4 11 1 110
|
|
5 1 1 10
|
|
10 1 1 10
|
|
11 100 1 1000
|
|
12 1000 1 10000
|
|
13 10000 1 100000
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
9
|
|
SELECT COUNT(c1) FROM t1;
|
|
COUNT(c1)
|
|
9
|
|
SELECT COUNT(c2) FROM t1;
|
|
COUNT(c2)
|
|
9
|
|
SELECT COUNT(c3) FROM t1;
|
|
COUNT(c3)
|
|
9
|
|
SELECT SUM(c1) FROM t1;
|
|
SUM(c1)
|
|
61
|
|
SELECT SUM(c2) FROM t1;
|
|
SUM(c2)
|
|
11128
|
|
SELECT AVG(c1), MAX(c1), MIN(c2), AVG(c3), SUM(c4) FROM t1;
|
|
AVG(c1) MAX(c1) MIN(c2) AVG(c3) SUM(c4)
|
|
6.7778 13 1 1.0000 111280
|
|
SELECT c1, c2 FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
c1 c2
|
|
5 1
|
|
10 1
|
|
11 100
|
|
12 1000
|
|
13 10000
|
|
SELECT COUNT(c2) FROM t1 WHERE c1 > ((SELECT COUNT(*) FROM t1) / 2);
|
|
COUNT(c2)
|
|
5
|
|
SELECT COUNT(*) FROM t1 WHERE c1 > (SELECT AVG(c1) FROM t1);
|
|
COUNT(*)
|
|
4
|
|
###############################################
|
|
#
|
|
# Try COUNT(*) on a DISCARDED table.
|
|
#
|
|
connection default;
|
|
CREATE TABLE t4 LIKE t1;
|
|
INSERT INTO t4 (SELECT * FROM t1);
|
|
SELECT COUNT(*) FROM t4;
|
|
COUNT(*)
|
|
9
|
|
ALTER TABLE t4 DISCARD TABLESPACE;
|
|
SELECT COUNT(*) FROM t4;
|
|
ERROR HY000: Tablespace has been discarded for table `t4`
|
|
#
|
|
# Test the interaction of a repeatable read transaction
|
|
# to changes that happen outside its view.
|
|
#
|
|
CREATE TABLE t5 (a INT AUTO_INCREMENT PRIMARY KEY, b TEXT, aa INT, bb TEXT) Engine=InnoDB;
|
|
INSERT INTO t5(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t5(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t5(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t5(b) VALUES ("inserted by client 1");
|
|
UPDATE t5 SET aa=a, bb=b;
|
|
CREATE TABLE t6 (a INT AUTO_INCREMENT PRIMARY KEY, b TEXT, aa INT, bb TEXT) Engine=InnoDB;
|
|
INSERT INTO t6(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t6(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t6(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t6(b) VALUES ("inserted by client 1");
|
|
UPDATE t6 SET aa=a, bb=b;
|
|
CREATE TABLE t7 (a INT AUTO_INCREMENT PRIMARY KEY, b TEXT, aa INT, bb TEXT) Engine=InnoDB;
|
|
INSERT INTO t7(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t7(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t7(b) VALUES ("inserted by client 1");
|
|
INSERT INTO t7(b) VALUES ("inserted by client 1");
|
|
UPDATE t7 SET aa=a, bb=b;
|
|
BEGIN;
|
|
SELECT * FROM t5;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
2 inserted by client 1 2 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
SELECT COUNT(*) FROM t5;
|
|
COUNT(*)
|
|
4
|
|
SELECT * FROM t6;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
2 inserted by client 1 2 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
SELECT COUNT(*) FROM t6;
|
|
COUNT(*)
|
|
4
|
|
SELECT * FROM t7;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
2 inserted by client 1 2 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
SELECT COUNT(*) FROM t7;
|
|
COUNT(*)
|
|
4
|
|
#
|
|
# Connection 1
|
|
#
|
|
connection con1;
|
|
INSERT INTO t5(b) VALUES ("inserted by client 2");
|
|
UPDATE t5 SET a = 10 where a = 1;
|
|
UPDATE t5 SET b = "updated by client 2" where a = 2;
|
|
DELETE FROM t5 WHERE a = 3;
|
|
SELECT * FROM t5;
|
|
a b aa bb
|
|
2 updated by client 2 2 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
5 inserted by client 2 NULL NULL
|
|
10 inserted by client 1 1 inserted by client 1
|
|
SELECT COUNT(*) FROM t5;
|
|
COUNT(*)
|
|
4
|
|
INSERT INTO t6(b) VALUES ("inserted by client 2");
|
|
UPDATE t6 SET a = 10 where a = 1;
|
|
UPDATE t6 SET b = "updated by client 2" where a = 2;
|
|
DELETE FROM t6 WHERE a = 3;
|
|
SELECT * FROM t6;
|
|
a b aa bb
|
|
2 updated by client 2 2 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
5 inserted by client 2 NULL NULL
|
|
10 inserted by client 1 1 inserted by client 1
|
|
SELECT COUNT(*) FROM t6;
|
|
COUNT(*)
|
|
4
|
|
INSERT INTO t7(b) VALUES ("inserted by client 2");
|
|
UPDATE t7 SET a = 10 where a = 1;
|
|
UPDATE t7 SET b = "updated by client 2" where a = 2;
|
|
DELETE FROM t7 WHERE a = 3;
|
|
SELECT * FROM t7;
|
|
a b aa bb
|
|
2 updated by client 2 2 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
5 inserted by client 2 NULL NULL
|
|
10 inserted by client 1 1 inserted by client 1
|
|
SELECT COUNT(*) FROM t7;
|
|
COUNT(*)
|
|
4
|
|
#
|
|
# Connection default
|
|
#
|
|
connection default;
|
|
SELECT * FROM t5;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
2 inserted by client 1 2 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
INSERT INTO t5(b) VALUES ("inserted by client 1");
|
|
SELECT * FROM t5;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
2 inserted by client 1 2 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
4 inserted by client 1 4 inserted by client 1
|
|
11 inserted by client 1 NULL NULL
|
|
UPDATE t5 SET a = a + 100;
|
|
SELECT * FROM t5;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
102 updated by client 2 2 inserted by client 1
|
|
104 inserted by client 1 4 inserted by client 1
|
|
105 inserted by client 2 NULL NULL
|
|
110 inserted by client 1 1 inserted by client 1
|
|
111 inserted by client 1 NULL NULL
|
|
SELECT COUNT(*) FROM t5;
|
|
COUNT(*)
|
|
7
|
|
UPDATE t6 SET b = "updated by client 2";
|
|
SELECT * FROM t6;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
2 inserted by client 1 2 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
4 updated by client 2 4 inserted by client 1
|
|
5 updated by client 2 NULL NULL
|
|
10 updated by client 2 1 inserted by client 1
|
|
SELECT * FROM t6 LOCK IN SHARE MODE;
|
|
a b aa bb
|
|
2 updated by client 2 2 inserted by client 1
|
|
4 updated by client 2 4 inserted by client 1
|
|
5 updated by client 2 NULL NULL
|
|
10 updated by client 2 1 inserted by client 1
|
|
SELECT COUNT(*) FROM t6;
|
|
COUNT(*)
|
|
6
|
|
DELETE FROM t7;
|
|
SELECT * FROM t7;
|
|
a b aa bb
|
|
1 inserted by client 1 1 inserted by client 1
|
|
3 inserted by client 1 3 inserted by client 1
|
|
SELECT COUNT(*) FROM t7;
|
|
COUNT(*)
|
|
2
|
|
COMMIT;
|
|
SELECT * FROM t5;
|
|
a b aa bb
|
|
102 updated by client 2 2 inserted by client 1
|
|
104 inserted by client 1 4 inserted by client 1
|
|
105 inserted by client 2 NULL NULL
|
|
110 inserted by client 1 1 inserted by client 1
|
|
111 inserted by client 1 NULL NULL
|
|
SELECT COUNT(*) FROM t5;
|
|
COUNT(*)
|
|
5
|
|
SELECT * FROM t6;
|
|
a b aa bb
|
|
2 updated by client 2 2 inserted by client 1
|
|
4 updated by client 2 4 inserted by client 1
|
|
5 updated by client 2 NULL NULL
|
|
10 updated by client 2 1 inserted by client 1
|
|
SELECT COUNT(*) FROM t6;
|
|
COUNT(*)
|
|
4
|
|
SELECT * FROM t7;
|
|
a b aa bb
|
|
SELECT COUNT(*) FROM t7;
|
|
COUNT(*)
|
|
0
|
|
#
|
|
# Cleanup
|
|
#
|
|
DROP TABLE t1,t2,t4,t5,t6,t7;
|
|
disconnect con1;
|
|
disconnect con2;
|
|
disconnect con3;
|
|
#
|
|
# Bug #23596760: FORCE INDEX IS SKIPPED WHILE EXECUTING SELECT COUNT(*)
|
|
#
|
|
CREATE TABLE t1(c1 INT NOT NULL PRIMARY KEY,
|
|
c2 INT NOT NULL DEFAULT 1,
|
|
c3 char(20) DEFAULT '',
|
|
KEY c2_idx (c2)) ENGINE=InnoDB;
|
|
INSERT INTO t1(c1) VALUES (1), (2), (3);
|
|
INSERT INTO t1(c1) SELECT c1 + 10 FROM t1;
|
|
INSERT INTO t1(c1) SELECT c1 + 100 FROM t1;
|
|
CREATE TABLE t2 SELECT * FROM t1;
|
|
EXPLAIN SELECT COUNT(*) FROM t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL c2_idx 4 NULL 12 Using index
|
|
EXPLAIN SELECT COUNT(*) FROM t1 FORCE INDEX(c2_idx);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL c2_idx 4 NULL 12 Using index
|
|
EXPLAIN SELECT COUNT(*) FROM t1, t2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL c2_idx 4 NULL 12 Using index
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 12 Using join buffer (flat, BNL join)
|
|
EXPLAIN SELECT COUNT(*) FROM t1 FORCE INDEX(c2_idx), t2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL c2_idx 4 NULL 12 Using index
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 12 Using join buffer (flat, BNL join)
|
|
DROP TABLE t1, t2;
|