From 6ac1930117741bb7847d35fcef5ecd83eff55857 Mon Sep 17 00:00:00 2001
From: calvin <>
Date: Thu, 24 Apr 2008 11:25:30 +0000
Subject: [PATCH] branches/5.1: Fix bug#29507 TRUNCATE shows to many rows
 effected

In InnoDB, the row count is only a rough estimate used by SQL
optimization. InnoDB is now return row count 0 for TRUNCATE operation.
---
 handler/ha_innodb.cc     |  7 +++++++
 mysql-test/innodb.result | 11 +++++++++++
 mysql-test/innodb.test   | 15 +++++++++++++++
 3 files changed, 33 insertions(+)

diff --git a/handler/ha_innodb.cc b/handler/ha_innodb.cc
index 67d9a9543f0..a52b1cb283c 100644
--- a/handler/ha_innodb.cc
+++ b/handler/ha_innodb.cc
@@ -5782,6 +5782,13 @@ ha_innobase::info(
 			n_rows++;
 		}
 
+		/* Fix bug#29507: TRUNCATE shows too many rows affected.
+		Do not show the estimates for TRUNCATE command. */
+		if (thd_sql_command(user_thd) == SQLCOM_TRUNCATE) {
+
+			n_rows = 0;
+		}
+
 		stats.records = (ha_rows)n_rows;
 		stats.deleted = 0;
 		stats.data_file_length = ((ulonglong)
diff --git a/mysql-test/innodb.result b/mysql-test/innodb.result
index 0cd276852bf..1ecf3ef5f60 100644
--- a/mysql-test/innodb.result
+++ b/mysql-test/innodb.result
@@ -3264,3 +3264,14 @@ AUTO_INCREMENT
 200
 DROP TABLE t2;
 DROP TABLE t1;
+CREATE TABLE t1 (c1 int default NULL,
+c2 int default NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1;
+TRUNCATE TABLE t1;
+affected rows: 0
+INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
+affected rows: 5
+info: Records: 5  Duplicates: 0  Warnings: 0
+TRUNCATE TABLE t1;
+affected rows: 0
+DROP TABLE t1;
diff --git a/mysql-test/innodb.test b/mysql-test/innodb.test
index d7c5f00564d..1073f5535df 100644
--- a/mysql-test/innodb.test
+++ b/mysql-test/innodb.test
@@ -2458,7 +2458,22 @@ SELECT AUTO_INCREMENT FROM INFORMATION_SCHEMA.TABLES WHERE table_name = 't2';
 DROP TABLE t2;
 DROP TABLE t1;
 # End 34920 test
+# Bug #29507 TRUNCATE shows to many rows effected
+#
+CONNECTION default;
+CREATE TABLE t1 (c1 int default NULL,
+		 c2 int default NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1;
 
+--enable_info
+TRUNCATE TABLE t1;
+
+INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
+TRUNCATE TABLE t1;
+
+--disable_info
+DROP TABLE t1;
+#
 #######################################################################
 #                                                                     #
 # Please, DO NOT TOUCH this file as well as the innodb.result file.   #