mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-01-31 02:51:44 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

manual.texi More SQL keyword capping.

Browse source
This commit is contained in:
paul@teton.kitebird.com 2002-04-22 10:24:27 -05:00
parent 5106b63d38
commit 464af126b8
1 changed files with 161 additions and 163 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

324
Docs/manual.texi
View file

@ -3499,7 +3499,7 @@ You can't use temporary tables more than once in the same query.
For example, the following doesn't work.
@example
select * from temporary_table, temporary_table as t2;
mysql> SELECT * FROM temporary_table, temporary_table AS t2;
@end example
@item
@ -3899,7 +3899,7 @@ Allow update of variables in @code{UPDATE} statements. For example:
@item
Change when user variables are updated so that one can use them with
@code{GROUP BY}, as in the following example:
@code{SELECT id, @@a:=count(*), sum(sum_col)/@@a FROM table_name GROUP BY id}.
@code{SELECT id, @@a:=COUNT(*), SUM(sum_col)/@@a FROM table_name GROUP BY id}.
@item
Don't add automatic @code{DEFAULT} values to columns. Give an error when using
an @code{INSERT} that doesn't contain a column that doesn't have a
@ -3930,7 +3930,7 @@ Make @code{LOAD DATA INFILE} understand syntax like:
@example
LOAD DATA INFILE 'file_name.txt' INTO TABLE tbl_name
TEXT_FIELDS (text_field1, text_field2, text_field3)
SET table_field1=concatenate(text_field1, text_field2),
SET table_field1=CONCAT(text_field1, text_field2),
table_field3=23
IGNORE text_field3
@end example
@ -3977,7 +3977,7 @@ should be implemented.
@item
@code{NATURAL JOIN}.
@item
Allow @code{select a from crash_me left join crash_me2 using (a)}; In this
Allow @code{SELECT a FROM crash_me LEFT JOIN crash_me2 USING (a)}; In this
case @code{a} is assumed to come from the @code{crash_me} table.
@item
Fix that @code{ON} and @code{USING} works with the @code{JOIN}
@ -4031,10 +4031,10 @@ value <> 0 -> TRUE.
@item
Fix that the type for @code{MAX(column)} is the same as the column type.
@example
create table t1 (a DATE);
insert into t1 values (now());
create table t2 select MAX(a) from t1;
show columns from t2;
mysql> CREATE TABLE t1 (a DATE);
mysql> INSERT INTO t1 VALUES (NOW());
mysql> CREATE TABLE t2 SELECT MAX(a) FROM t1;
mysql> SHOW COLUMNS FROM t2;
@end example
@item
Come up with a nice syntax for a statement that will @code{UPDATE} the row
@ -7664,7 +7664,7 @@ Database: mysql
| user |
+--------------+
shell> BINDIR/mysql -e "select host,db,user from db" mysql
shell> BINDIR/mysql -e "SELECT host,db,user FROM db" mysql
+------+--------+------+
| host | db | user |
+------+--------+------+
@ -11578,7 +11578,7 @@ prompt and press Enter:
@example
mysql> SELECT VERSION(), CURRENT_DATE;
+--------------+--------------+
| version() | CURRENT_DATE |
| VERSION() | CURRENT_DATE |
+--------------+--------------+
| 3.22.20a-log | 1999-03-19 |
+--------------+--------------+
@ -11644,7 +11644,7 @@ Just end each one with a semicolon:
@example
mysql> SELECT VERSION(); SELECT NOW();
+--------------+
| version() |
| VERSION() |
+--------------+
| 3.22.20a-log |
+--------------+
@ -13439,9 +13439,8 @@ For example, to find the articles with the highest and lowest price you
can do:
@example
select @@min_price:=min(price),@@max_price:=max(price) from shop;
select * from shop where price=@@min_price or price=@@max_price;
mysql> SELECT @@min_price:=MIN(price),@@max_price:=MAX(price) FROM shop;
mysql> SELECT * FROM shop WHERE price=@@min_price OR price=@@max_price;
+---------+--------+-------+
| article | dealer | price |
+---------+--------+-------+
@ -13663,8 +13662,8 @@ Which returns:
+--------+----+---------+
@end example
Note that in this case, the auto_increment value will be reused if you
delete the row with the biggest auto_increment value in any group.
Note that in this case, the @code{AUTO_INCREMENT} value will be reused if you
delete the row with the biggest @code{AUTO_INCREMENT} value in any group.
You can get the used @code{AUTO_INCREMENT} key with the
@code{LAST_INSERT_ID()} SQL function or the @code{mysql_insert_id()} API
@ -13832,96 +13831,96 @@ The following query is used to determine who goes into the second part of the
project:
@example
select
concat(p1.id, p1.tvab) + 0 as tvid,
concat(p1.christian_name, " ", p1.surname) as Name,
p1.postal_code as Code,
p1.city as City,
pg.abrev as Area,
if(td.participation = "Aborted", "A", " ") as A,
p1.dead as dead1,
l.event as event1,
td.suspect as tsuspect1,
id.suspect as isuspect1,
td.severe as tsevere1,
id.severe as isevere1,
p2.dead as dead2,
l2.event as event2,
h2.nurse as nurse2,
h2.doctor as doctor2,
td2.suspect as tsuspect2,
id2.suspect as isuspect2,
td2.severe as tsevere2,
id2.severe as isevere2,
SELECT
CONCAT(p1.id, p1.tvab) + 0 AS tvid,
CONCAT(p1.christian_name, " ", p1.surname) AS Name,
p1.postal_code AS Code,
p1.city AS City,
pg.abrev AS Area,
IF(td.participation = "Aborted", "A", " ") AS A,
p1.dead AS dead1,
l.event AS event1,
td.suspect AS tsuspect1,
id.suspect AS isuspect1,
td.severe AS tsevere1,
id.severe AS isevere1,
p2.dead AS dead2,
l2.event AS event2,
h2.nurse AS nurse2,
h2.doctor AS doctor2,
td2.suspect AS tsuspect2,
id2.suspect AS isuspect2,
td2.severe AS tsevere2,
id2.severe AS isevere2,
l.finish_date
from
twin_project as tp
FROM
twin_project AS tp
/* For Twin 1 */
left join twin_data as td on tp.id = td.id
and tp.tvab = td.tvab
left join informant_data as id on tp.id = id.id
and tp.tvab = id.tvab
left join harmony as h on tp.id = h.id
and tp.tvab = h.tvab
left join lentus as l on tp.id = l.id
and tp.tvab = l.tvab
LEFT JOIN twin_data AS td ON tp.id = td.id
AND tp.tvab = td.tvab
LEFT JOIN informant_data AS id ON tp.id = id.id
AND tp.tvab = id.tvab
LEFT JOIN harmony AS h ON tp.id = h.id
AND tp.tvab = h.tvab
LEFT JOIN lentus AS l ON tp.id = l.id
AND tp.tvab = l.tvab
/* For Twin 2 */
left join twin_data as td2 on p2.id = td2.id
and p2.tvab = td2.tvab
left join informant_data as id2 on p2.id = id2.id
and p2.tvab = id2.tvab
left join harmony as h2 on p2.id = h2.id
and p2.tvab = h2.tvab
left join lentus as l2 on p2.id = l2.id
and p2.tvab = l2.tvab,
person_data as p1,
person_data as p2,
postal_groups as pg
where
LEFT JOIN twin_data AS td2 ON p2.id = td2.id
AND p2.tvab = td2.tvab
LEFT JOIN informant_data AS id2 ON p2.id = id2.id
AND p2.tvab = id2.tvab
LEFT JOIN harmony AS h2 ON p2.id = h2.id
AND p2.tvab = h2.tvab
LEFT JOIN lentus AS l2 ON p2.id = l2.id
AND p2.tvab = l2.tvab,
person_data AS p1,
person_data AS p2,
postal_groups AS pg
WHERE
/* p1 gets main twin and p2 gets his/her twin. */
/* ptvab is a field inverted from tvab */
p1.id = tp.id and p1.tvab = tp.tvab and
p2.id = p1.id and p2.ptvab = p1.tvab and
p1.id = tp.id AND p1.tvab = tp.tvab AND
p2.id = p1.id AND p2.ptvab = p1.tvab AND
/* Just the sceening survey */
tp.survey_no = 5 and
tp.survey_no = 5 AND
/* Skip if partner died before 65 but allow emigration (dead=9) */
(p2.dead = 0 or p2.dead = 9 or
(p2.dead = 1 and
(p2.death_date = 0 or
(((to_days(p2.death_date) - to_days(p2.birthday)) / 365)
(p2.dead = 0 OR p2.dead = 9 OR
(p2.dead = 1 AND
(p2.death_date = 0 OR
(((TO_DAYS(p2.death_date) - TO_DAYS(p2.birthday)) / 365)
>= 65))))
and
AND
(
/* Twin is suspect */
(td.future_contact = 'Yes' and td.suspect = 2) or
(td.future_contact = 'Yes' AND td.suspect = 2) OR
/* Twin is suspect - Informant is Blessed */
(td.future_contact = 'Yes' and td.suspect = 1
and id.suspect = 1) or
(td.future_contact = 'Yes' AND td.suspect = 1
AND id.suspect = 1) OR
/* No twin - Informant is Blessed */
(ISNULL(td.suspect) and id.suspect = 1
and id.future_contact = 'Yes') or
(ISNULL(td.suspect) AND id.suspect = 1
AND id.future_contact = 'Yes') OR
/* Twin broken off - Informant is Blessed */
(td.participation = 'Aborted'
and id.suspect = 1 and id.future_contact = 'Yes') or
AND id.suspect = 1 AND id.future_contact = 'Yes') OR
/* Twin broken off - No inform - Have partner */
(td.participation = 'Aborted' and ISNULL(id.suspect)
and p2.dead = 0))
and
(td.participation = 'Aborted' AND ISNULL(id.suspect)
AND p2.dead = 0))
AND
l.event = 'Finished'
/* Get at area code */
and substring(p1.postal_code, 1, 2) = pg.code
AND SUBSTRING(p1.postal_code, 1, 2) = pg.code
/* Not already distributed */
and (h.nurse is NULL or h.nurse=00 or h.doctor=00)
AND (h.nurse IS NULL OR h.nurse=00 OR h.doctor=00)
/* Has not refused or been aborted */
and not (h.status = 'Refused' or h.status = 'Aborted'
or h.status = 'Died' or h.status = 'Other')
order by
AND NOT (h.status = 'Refused' OR h.status = 'Aborted'
OR h.status = 'Died' OR h.status = 'Other')
ORDER BY
tvid;
@end example
Some explanations:
@table @asis
@item @code{concat(p1.id, p1.tvab) + 0 as tvid}
@item @code{CONCAT(p1.id, p1.tvab) + 0 AS tvid}
We want to sort on the concatenated @code{id} and @code{tvab} in
numerical order. Adding @code{0} to the result causes MySQL to
treat the result as a number.
@ -13969,24 +13968,24 @@ event. This indicates in how many pairs both twins are finished, in how many
pairs one twin is finished and the other refused, and so on.
@example
select
SELECT
t1.event,
t2.event,
count(*)
from
lentus as t1,
lentus as t2,
twin_project as tp
where
COUNT(*)
FROM
lentus AS t1,
lentus AS t2,
twin_project AS tp
WHERE
/* We are looking at one pair at a time */
t1.id = tp.id
and t1.tvab=tp.tvab
and t1.id = t2.id
AND t1.tvab=tp.tvab
AND t1.id = t2.id
/* Just the sceening survey */
and tp.survey_no = 5
AND tp.survey_no = 5
/* This makes each pair only appear once */
and t1.tvab='1' and t2.tvab='2'
group by
AND t1.tvab='1' AND t2.tvab='2'
GROUP BY
t1.event, t2.event;
@end example
@ -17642,14 +17641,14 @@ Some things reported by check table, can't be corrected automatically:
@code{Found row where the auto_increment column has the value 0}.
This means that you have in the table a row where the
@code{auto_increment} index column contains the value 0.
(It's possible to create a row where the auto_increment column is 0 by
@code{AUTO_INCREMENT} index column contains the value 0.
(It's possible to create a row where the @code{AUTO_INCREMENT} column is 0 by
explicitly setting the column to 0 with an @code{UPDATE} statement)
This isn't an error in itself, but could cause trouble if you decide to
dump the table and restore it or do an @code{ALTER TABLE} on the
table. In this case the auto_increment column will change value,
according to the rules of auto_increment columns, which could cause
table. In this case the @code{AUTO_INCREMENT} column will change value,
according to the rules of @code{AUTO_INCREMENT} columns, which could cause
problems like a duplicate key error.
To get rid of the warning, just execute an @code{UPDATE} statement
@ -18032,8 +18031,8 @@ MySQL.
@item -d or --description
Prints some information about table.
@item -A or --set-auto-increment[=value]
Force auto_increment to start at this or higher value. If no value is
given, then sets the next auto_increment value to the highest used value
Force @code{AUTO_INCREMENT} to start at this or higher value. If no value is
given, then sets the next @code{AUTO_INCREMENT} value to the highest used value
for the auto key + 1.
@item -S or --sort-index
Sort the index tree blocks in high-low order.
@ -24386,10 +24385,10 @@ query from the master.
@item
If you have decided you can skip the next query, do
@code{SET SQL_SLAVE_SKIP_COUNTER=1; SLAVE START;} to skip a query that
does not use auto_increment, or last_insert_id or
does not use @code{AUTO_INCREMENT} or @code{LAST_INSERT_ID()}, or
@code{SET SQL_SLAVE_SKIP_COUNTER=2; SLAVE START;} otherwise. The reason
auto_increment/last_insert_id queries are different is that they take
two events in the binary log of the master.
queries that use @code{AUTO_INCREMENT} or @code{LAST_INSERT_ID()}
are different is that they take two events in the binary log of the master.
@item
If you are sure the slave started out perfectly in sync with the master,
@ -25928,7 +25927,7 @@ In some cases it may make sense to introduce a column that is 'hashed'
based on information from other columns. If this column is short and
reasonably unique it may be much faster than a big index on many
columns. In MySQL it's very easy to use this extra column:
@code{SELECT * FROM table_name WHERE hash=MD5(concat(col1,col2))
@code{SELECT * FROM table_name WHERE hash=MD5(CONCAT(col1,col2))
AND col_1='constant' AND col_2='constant'}
@item
For tables that change a lot you should try to avoid all @code{VARCHAR}
@ -27302,7 +27301,7 @@ mysql> UPDATE mysql.user SET password=PASSWORD("newpass")
@item SQL_AUTO_IS_NULL = 0 | 1
If set to @code{1} (default) then one can find the last inserted row
for a table with an auto_increment row with the following construct:
for a table with an @code{AUTO_INCREMENT} column with the following construct:
@code{WHERE auto_increment_column IS NULL}. This is used by some
ODBC programs like Access.
@ -29490,7 +29489,7 @@ object. The standard way to do this is with the @code{SUBSTRING}
function. For example:
@example
mysql> SELECT comment FROM tbl_name,substring(comment,20) AS substr
mysql> SELECT comment FROM tbl_name,SUBSTRING(comment,20) AS substr
-> ORDER BY substr;
@end example
@ -32612,7 +32611,7 @@ the same @code{INSERT} statement against some other server.
If @code{expr} is given as an argument to @code{LAST_INSERT_ID()}, then
the value of the argument is returned by the function, is set as the
next value to be returned by @code{LAST_INSERT_ID()} and used as the next
auto_increment value. This can be used to simulate sequences:
@code{AUTO_INCREMENT} value. This can be used to simulate sequences:
First create the table:
@ -32729,7 +32728,7 @@ use is in the @code{mysql} client, which reports query execution times:
@example
mysql> SELECT BENCHMARK(1000000,ENCODE("hello","goodbye"));
+----------------------------------------------+
| BENCHMARK(1000000,encode("hello","goodbye")) |
| BENCHMARK(1000000,ENCODE("hello","goodbye")) |
+----------------------------------------------+
| 0 |
+----------------------------------------------+
@ -32909,7 +32908,7 @@ grouping on unnecessary items. For example, you don't need to group on
@code{customer.name} in the following query:
@example
mysql> SELECT order.custid,customer.name,max(payments)
mysql> SELECT order.custid,customer.name,MAX(payments)
-> FROM order,customer
-> WHERE order.custid = customer.custid
-> GROUP BY order.custid;
@ -32929,7 +32928,7 @@ column value even if it isn't unique. The following gives the value of
column:
@example
substr(MIN(concat(rpad(sort,6,' '),column)),7)
SUBSTR(MIN(CONCAT(RPAD(sort,6,' '),column)),7)
@end example
@xref{example-Maximum-column-group-row}.
@ -33119,7 +33118,7 @@ In MySQL Version 3.22.5 or later, you can also write queries like this:
@example
mysql> SELECT user,MAX(salary) FROM users
-> group by user HAVING max(salary)>10;
-> GROUP BY user HAVING MAX(salary)>10;
@end example
In older MySQL versions, you can write this instead:
@ -34355,10 +34354,10 @@ For example, to read a file of jokes, that are separated with a line
of @code{%%}, into a SQL table you can do:
@example
create table jokes (a int not null auto_increment primary key, joke text
not null);
load data infile "/tmp/jokes.txt" into table jokes fields terminated by ""
lines terminated by "\n%%\n" (joke);
CREATE TABLE jokes (a INT NOT NULL AUTO_INCREMENT PRIMARY KEY, joke TEXT
NOT NULL);
LOAD DATA INFILE "/tmp/jokes.txt" INTO TABLE jokes FIELDS TERMINATED BY ""
LINES TERMINATED BY "\n%%\n" (joke);
@end example
@code{FIELDS [OPTIONALLY] ENCLOSED BY} controls quoting of fields. For
@ -34852,11 +34851,11 @@ with @code{DELETE FROM table_name} (without a @code{WHERE}) in
@strong{NOTE:} There can be only one @code{AUTO_INCREMENT} column per
table, and it must be indexed. MySQL Version 3.23 will also only
work properly if the auto_increment column only has positive
work properly if the @code{AUTO_INCREMENT} column only has positive
values. Inserting a negative number is regarded as inserting a very large
positive number. This is done to avoid precision problems when
numbers 'wrap' over from positive to negative and also to ensure that one
doesn't accidentally get an auto_increment column that contains 0.
doesn't accidentally get an @code{AUTO_INCREMENT} column that contains 0.
In MyISAM and BDB tables you can specify @code{AUTO_INCREMENT} secondary
column in a multi-column key. @xref{example-AUTO_INCREMENT}.
@ -34980,7 +34979,7 @@ Only the @code{MyISAM} table type supports indexing on @code{BLOB} and
@code{TEXT} columns. When putting an index on a @code{BLOB} or @code{TEXT}
column you MUST always specify the length of the index:
@example
CREATE TABLE test (blob_col BLOB, index(blob_col(10)));
CREATE TABLE test (blob_col BLOB, INDEX(blob_col(10)));
@end example
@item
@ -35046,7 +35045,7 @@ The options work for all table types, if not otherwise indicated:
@multitable @columnfractions .25 .75
@item @strong{Option} @tab @strong{Description}
@item @code{AUTO_INCREMENT} @tab The next auto_increment value you want to set for your table (MyISAM).
@item @code{AUTO_INCREMENT} @tab The next @code{AUTO_INCREMENT} value you want to set for your table (MyISAM).
@item @code{AVG_ROW_LENGTH} @tab An approximation of the average row length for your table. You only need to set this for large tables with variable size records.
@item @code{CHECKSUM} @tab Set this to 1 if you want MySQL to maintain a checksum for all rows (makes the table a little slower to update but makes it easier to find corrupted tables) (MyISAM).
@item @code{COMMENT} @tab A 60-character comment for your table.
@ -35689,9 +35688,9 @@ is issued:
@example
mysql> USE db1;
mysql> SELECT count(*) FROM mytable; # selects from db1.mytable
mysql> SELECT COUNT(*) FROM mytable; # selects from db1.mytable
mysql> USE db2;
mysql> SELECT count(*) FROM mytable; # selects from db2.mytable
mysql> SELECT COUNT(*) FROM mytable; # selects from db2.mytable
@end example
Making a particular database current by means of the @code{USE} statement
@ -37233,7 +37232,6 @@ INSERT INTO t2 (message) VALUES ("Testing"),("table"),("t2");
CREATE TABLE total (a INT NOT NULL, message CHAR(20), KEY(a))
TYPE=MERGE UNION=(t1,t2) INSERT_METHOD=LAST;
@end example
@c CAPPING DONE TO HERE
Note that we didn't create a @code{UNIQUE} or @code{PRIMARY KEY} in the
@code{total} table as the key isn't going to be unique in the @code{total}
@ -37251,7 +37249,7 @@ shell> mysqladmin flush-tables
Now you can do things like:
@example
mysql> select * from total;
mysql> SELECT * FROM total;
+---+---------+
| a | message |
+---+---------+
@ -37384,7 +37382,7 @@ without overflow areas. There is no extra space needed for free lists.
normally is common with hashed tables:
@example
mysql> CREATE TABLE test TYPE=HEAP SELECT ip,SUM(downloads) as down
mysql> CREATE TABLE test TYPE=HEAP SELECT ip,SUM(downloads) AS down
-> FROM log_table GROUP BY ip;
mysql> SELECT COUNT(ip),AVG(down) FROM test;
mysql> DROP TABLE test;
@ -46305,8 +46303,8 @@ You have specified a password in the @code{user} table without using the
function:
@example
mysql> update user set password=PASSWORD('your password')
-> where user='XXX';
mysql> UPDATE user SET password=PASSWORD('your password')
-> WHERE user='XXX';
@end example
@end itemize
@ -47116,7 +47114,7 @@ mysql> INSERT INTO tbl_name (idate) VALUES ('0000-00-00');
mysql> SELECT idate FROM tbl_name WHERE idate >= '1997-05-05';
mysql> SELECT idate FROM tbl_name WHERE idate >= 19970505;
mysql> SELECT mod(idate,100) FROM tbl_name WHERE idate >= 19970505;
mysql> SELECT MOD(idate,100) FROM tbl_name WHERE idate >= 19970505;
mysql> SELECT idate FROM tbl_name WHERE idate >= '19970505';
@end example
@ -47565,7 +47563,7 @@ You can't use temporary tables more than once in the same query.
For example, the following doesn't work.
@example
select * from temporary_table, temporary_table as t2;
mysql> SELECT * FROM temporary_table, temporary_table AS t2;
@end example
We plan to fix the above in 4.0.
@ -51822,7 +51820,7 @@ Fixed problem when using an @code{AUTO_INCREMENT} column in two keys
@item
With @code{MyISAM}, you now can have an @code{AUTO_INCREMENT} column as a key
sub part:
@code{CREATE TABLE foo (a int not null auto_increment, b char(5), primary key (b,a))}
@code{CREATE TABLE foo (a INT NOT NULL AUTO_INCREMENT, b CHAR(5), PRIMARY KEY (b,a))}
@item
Fixed bug in @code{MyISAM} with packed char keys that could be @code{NULL}.
@item
@ -56157,57 +56155,57 @@ characters/constructs:
@item ^
Match the beginning of a string.
@example
mysql> select "fo\nfo" REGEXP "^fo$"; -> 0
mysql> select "fofo" REGEXP "^fo"; -> 1
mysql> SELECT "fo\nfo" REGEXP "^fo$"; -> 0
mysql> SELECT "fofo" REGEXP "^fo"; -> 1
@end example
@item $
Match the end of a string.
@example
mysql> select "fo\no" REGEXP "^fo\no$"; -> 1
mysql> select "fo\no" REGEXP "^fo$"; -> 0
mysql> SELECT "fo\no" REGEXP "^fo\no$"; -> 1
mysql> SELECT "fo\no" REGEXP "^fo$"; -> 0
@end example
@item .
Match any character (including newline).
@example
mysql> select "fofo" REGEXP "^f.*"; -> 1
mysql> select "fo\nfo" REGEXP "^f.*"; -> 1
mysql> SELECT "fofo" REGEXP "^f.*"; -> 1
mysql> SELECT "fo\nfo" REGEXP "^f.*"; -> 1
@end example
@item a*
Match any sequence of zero or more @code{a} characters.
@example
mysql> select "Ban" REGEXP "^Ba*n"; -> 1
mysql> select "Baaan" REGEXP "^Ba*n"; -> 1
mysql> select "Bn" REGEXP "^Ba*n"; -> 1
mysql> SELECT "Ban" REGEXP "^Ba*n"; -> 1
mysql> SELECT "Baaan" REGEXP "^Ba*n"; -> 1
mysql> SELECT "Bn" REGEXP "^Ba*n"; -> 1
@end example
@item a+
Match any sequence of one or more @code{a} characters.
@example
mysql> select "Ban" REGEXP "^Ba+n"; -> 1
mysql> select "Bn" REGEXP "^Ba+n"; -> 0
mysql> SELECT "Ban" REGEXP "^Ba+n"; -> 1
mysql> SELECT "Bn" REGEXP "^Ba+n"; -> 0
@end example
@item a?
Match either zero or one @code{a} character.
@example
mysql> select "Bn" REGEXP "^Ba?n"; -> 1
mysql> select "Ban" REGEXP "^Ba?n"; -> 1
mysql> select "Baan" REGEXP "^Ba?n"; -> 0
mysql> SELECT "Bn" REGEXP "^Ba?n"; -> 1
mysql> SELECT "Ban" REGEXP "^Ba?n"; -> 1
mysql> SELECT "Baan" REGEXP "^Ba?n"; -> 0
@end example
@item de|abc
Match either of the sequences @code{de} or @code{abc}.
@example
mysql> select "pi" REGEXP "pi|apa"; -> 1
mysql> select "axe" REGEXP "pi|apa"; -> 0
mysql> select "apa" REGEXP "pi|apa"; -> 1
mysql> select "apa" REGEXP "^(pi|apa)$"; -> 1
mysql> select "pi" REGEXP "^(pi|apa)$"; -> 1
mysql> select "pix" REGEXP "^(pi|apa)$"; -> 0
mysql> SELECT "pi" REGEXP "pi|apa"; -> 1
mysql> SELECT "axe" REGEXP "pi|apa"; -> 0
mysql> SELECT "apa" REGEXP "pi|apa"; -> 1
mysql> SELECT "apa" REGEXP "^(pi|apa)$"; -> 1
mysql> SELECT "pi" REGEXP "^(pi|apa)$"; -> 1
mysql> SELECT "pix" REGEXP "^(pi|apa)$"; -> 0
@end example
@item (abc)*
Match zero or more instances of the sequence @code{abc}.
@example
mysql> select "pi" REGEXP "^(pi)*$"; -> 1
mysql> select "pip" REGEXP "^(pi)*$"; -> 0
mysql> select "pipi" REGEXP "^(pi)*$"; -> 1
mysql> SELECT "pi" REGEXP "^(pi)*$"; -> 1
mysql> SELECT "pip" REGEXP "^(pi)*$"; -> 0
mysql> SELECT "pipi" REGEXP "^(pi)*$"; -> 1
@end example
@item @{1@}
@itemx @{2,3@}
@ -56243,12 +56241,12 @@ literal @code{-} character, it must be written first or last. So
a defined meaning inside a @code{[]} pair has no special meaning and
matches only itself.
@example
mysql> select "aXbc" REGEXP "[a-dXYZ]"; -> 1
mysql> select "aXbc" REGEXP "^[a-dXYZ]$"; -> 0
mysql> select "aXbc" REGEXP "^[a-dXYZ]+$"; -> 1
mysql> select "aXbc" REGEXP "^[^a-dXYZ]+$"; -> 0
mysql> select "gheis" REGEXP "^[^a-dXYZ]+$"; -> 1
mysql> select "gheisa" REGEXP "^[^a-dXYZ]+$"; -> 0
mysql> SELECT "aXbc" REGEXP "[a-dXYZ]"; -> 1
mysql> SELECT "aXbc" REGEXP "^[a-dXYZ]$"; -> 0
mysql> SELECT "aXbc" REGEXP "^[a-dXYZ]+$"; -> 1
mysql> SELECT "aXbc" REGEXP "^[^a-dXYZ]+$"; -> 0
mysql> SELECT "gheis" REGEXP "^[^a-dXYZ]+$"; -> 1
mysql> SELECT "gheisa" REGEXP "^[^a-dXYZ]+$"; -> 0
@end example
@item [[.characters.]]
The sequence of characters of that collating element. The sequence is a
@ -56284,8 +56282,8 @@ These stand for the character classes defined in the @code{ctype(3)} manual
page. A locale may provide others. A character class may not be used as an
endpoint of a range.
@example
mysql> select "justalnums" REGEXP "[[:alnum:]]+"; -> 1
mysql> select "!!" REGEXP "[[:alnum:]]+"; -> 0
mysql> SELECT "justalnums" REGEXP "[[:alnum:]]+"; -> 1
mysql> SELECT "!!" REGEXP "[[:alnum:]]+"; -> 0
@end example
@item [[:<:]]
@ -56296,13 +56294,13 @@ is neither preceded nor followed by word characters. A word character is
an alnum character (as defined by @code{ctype(3)}) or an underscore
(@code{_}).
@example
mysql> select "a word a" REGEXP "[[:<:]]word[[:>:]]"; -> 1
mysql> select "a xword a" REGEXP "[[:<:]]word[[:>:]]"; -> 0
mysql> SELECT "a word a" REGEXP "[[:<:]]word[[:>:]]"; -> 1
mysql> SELECT "a xword a" REGEXP "[[:<:]]word[[:>:]]"; -> 0
@end example
@end table
@example
mysql> select "weeknights" REGEXP "^(wee|week)(knights|nights)$"; -> 1
mysql> SELECT "weeknights" REGEXP "^(wee|week)(knights|nights)$"; -> 1
@end example