sql server 与mysql差异(innodb)

MySQL	SQL SERVER
CHAR_LENGTH(str)	LEN(character_expression)
CONCAT(str1,str2,...)	str1+str2
INSERT(str,pos,len,newstr)	STUFF ( character_expression , start , length ,character_expression )
LOCATE(substr,str [,pos])	CHARINDEX ( expression1 ,expression2 [ , start_location ] )
LEFT(str,len)	LEFT ( character_expression , integer_expression )
LENGTH(str)	DATALENGTH ( expression )
LTRIM(str)	LTRIM(character expression)
REPEAT(str,count)	REPLICATE(character_expression,times)
REPLACE(str,from_str,to_str)	REPLACE(character_expression,searchstring,replacementstring)
REVERSE(str)	REVERSE(character_expression)
RIGHT(str,len)	RIGHT(character_expression,integer_expression)
RTRIM(str)	RTRIM(character expression)
SUBSTRING(str,pos,len) SUBSTRING(str FROM pos FOR len)	SUBSTRING(character_expression, position, length)
SUBSTRING_INDEX(str,delim,count)	无
TRIM([{BOTH | LEADING | TRAILING} [remstr] FROM] str) TRIM([remstr FROM] str)	无

MySQL	SQL SERVER
CURDATE()	无
CURTIME()	无
DATE(expr)	无
DATE_ADD(date,INTERVAL expr unit) DATE_SUB(date,INTERVAL expr unit)	DATEADD(datepart, number, date)
DAY(date)	DATEPART('dd', date)
HOUR(time)	DATEPART('hh', date)
MINUTE(time)	DATEPART('mi', date)
MONTH(date)	DATEPART('mm', date)
NOW()	GETDATE()
SECOND(time)	DATEPART('ss', date)
TIME(expr)	无
YEAR(date)	DATEPART('yy', date)

v在创建视图时需要注意：

如果表Test中有A、B两个字段，创建视图如下

Create view v_test as select * from Test;

此时视图实际的定义如下：

Create view v_test as select A,B from Test;

也就是说Test将来增加的字段并不在视图里面。

在SQL SERVER中，如果创建视图如下

Create view v_test as select * from Test;

此时视图实际的定义就是：

Create view v_test as select * from Test;

视图中永远都包含Test的所有字段。