有关 ANSI_NULLS 数据库选项的详细信息,请参阅 ALTER DATABASE (Transact-SQL) 和设置数据库选项。 仅当某个比较操作数是值为 NULL 的变量或文字 NULL 时,SET ANSI_NULLS ON 才会影响比较。如果比较双方是列或复合表达式,则该设置不会影响比较。 为使脚本按预期运行,不管 ANSI_NULLS 数据库选项或 SET ANSI_...
GROUP BY ELT(INTERVAL(d.yb, 0, 100, 500, 1000), '1/less100', '2/100to500', '3/500to1000', '4/more1000K'); # COUNT 带条件计数 # count(*) 包含 null 值的条目,count(字段) 则不包含 null的字段 SELECT COUNT(yb > 200 OR NULL) FROM k1; # 2 SELECT COUNT(IF(yb > 200, 1,...
{ ON | OFF } | MEMORY_OPTIMIZED_ELEVATE_TO_SNAPSHOT = { ON | OFF } } <sql_option> ::= { ANSI_NULL_DEFAULT { ON | OFF } | ANSI_NULLS { ON | OFF } | ANSI_PADDING { ON | OFF } | ANSI_WARNINGS { ON | OFF } | ARITHABORT { ON | OFF } | COMPATIBILITY_LEVEL = { 160...
INSERT INTO t1 (a) VALUES (NULL); GO -- SET ANSI_NULL_DFLT_ON to ON and create table t2. SET ANSI_NULL_DFLT_ON ON; GO CREATE TABLE t2 (a TINYINT); GO -- NULL insert should succeed. INSERT INTO t2 (a) VALUES (NULL); GO -- SET ANSI_NULL_DFLT_ON to OFF...
{ ON | OFF } | MEMORY_OPTIMIZED_ELEVATE_TO_SNAPSHOT = { ON | OFF } } <sql_option> ::= { ANSI_NULL_DEFAULT { ON | OFF } | ANSI_NULLS { ON | OFF } | ANSI_PADDING { ON | OFF } | ANSI_WARNINGS { ON | OFF } | ARITHABORT ...
如果将 CONCAT_NULL_YIELDS_NULL 设置为 OFF,则不能出现跨服务器边界的字符串串联。 要查看此设置的当前设置,请运行以下查询。 SQL DECLARE@CONCAT_SETTINGVARCHAR(3) ='OFF'; IF ( (4096 & @@OPTIONS) = 4096 )SET@CONCAT_SETTING ='ON';SELECT@CONCAT_SETTINGASCONCAT_NULL_YIELDS_NULL; ...
() || /* The empty transactions do not need to clear the writeset history, since they can be executed in parallel. */ is_empty_transaction_in_binlog_cache(thd)) && // hashing algorithm for the session must be the same as used by other // rows in history (global_system_variables....
mysql导入sql文件失败 报错:Variable 'time_zone' can't be set to the value of 'Null' Mysql配置文件(/etc/mysql/conf.d/my.conf)添加: max_allowed_packet=1024M 重启Mysql服务: systemctl restart mysql
SQL CREATETABLEdbo.Tool (IDINTIDENTITYNOTNULLPRIMARYKEY,NameVARCHAR(40)NOTNULL); GO 将值插入产品表中。 SQL INSERTINTOdbo.Tool (Name)VALUES('Screwdriver'), ('Hammer'), ('Saw'), ('Shovel'); GO 在标识值中创建空白。 SQL DELETEdbo.ToolWHEREName='Saw'; GOSELECT*FROMdbo.Tool; GO ...
// they punt and go back to mysql_store_results() behavior // if (this.connection.versionMeetsMinimum(5, 0, 5)) { usingCursor = (this.serverStatus & SERVER_STATUS_CURSOR_EXISTS) != 0; } if (usingCursor) { RowData rows = new RowDataCursor( ...