41 lines
1.4 KiB
Plaintext
41 lines
1.4 KiB
Plaintext
drop table if exists t1;
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set @@session.sql_auto_is_null=1;
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select {fn length("hello")}, { date "1997-10-20" };
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{fn length("hello")} 1997-10-20
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5 1997-10-20
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create table t1 (a int not null auto_increment,b int not null,primary key (a,b));
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insert into t1 SET A=NULL,B=1;
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insert into t1 SET a=null,b=2;
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select * from t1 where a is null and b=2;
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a b
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select * from t1 where a is null;
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a b
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2 2
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analyze table t1;
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Table Op Msg_type Msg_text
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test.t1 analyze status OK
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explain select * from t1 where b is null;
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
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Warnings:
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Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where 0
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drop table t1;
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CREATE TABLE t1 (a INT AUTO_INCREMENT PRIMARY KEY);
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INSERT INTO t1 VALUES (NULL);
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SELECT sql_no_cache a, last_insert_id() FROM t1 WHERE a IS NULL;
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a last_insert_id()
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1 1
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Warnings:
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Warning 1681 'SQL_NO_CACHE' is deprecated and will be removed in a future release.
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SELECT sql_no_cache a, last_insert_id() FROM t1 WHERE a IS NULL;
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a last_insert_id()
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Warnings:
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Warning 1681 'SQL_NO_CACHE' is deprecated and will be removed in a future release.
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SELECT sql_no_cache a, last_insert_id() FROM t1;
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a last_insert_id()
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1 1
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Warnings:
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Warning 1681 'SQL_NO_CACHE' is deprecated and will be removed in a future release.
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DROP TABLE t1;
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set @@session.sql_auto_is_null=default;
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