SQL Ñ»·
declare @i int
set @i=1
while @i<30
begin
insert into test (userid) values(@i)
set @i=@i+1
end
---------------
while Ìõ¼þ
begin
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set @i=@i+1
end
WHILE
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WHILE Boolean_expression
{ sql_statement | statement_block }
[ BREAK ]
{ sql_statement | statement_block }
[ CONTINUE ]
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Boolean_expression
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{sql_statement | statement_block}
Transact-SQL Óï¾ä»òÓÃÓï¾ä¿é¶¨ÒåµÄÓï¾ä·Ö×é¡£ÈôÒª¶¨ÒåÓï¾ä¿é£¬ÇëʹÓÿØÖÆÁ÷¹Ø¼ü×Ö BEGIN ºÍ END¡£
BREAK
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CONTINUE
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A. ÔÚǶÌ×µÄ IF...ELSE ºÍ WHILE ÖÐʹÓà BREAK ºÍ CONTINUE
ÔÚÏÂÀýÖУ¬Èç¹ûƽ¾ù¼Û¸ñÉÙÓÚ $30£¬WHILE Ñ»·¾Í½«¼Û¸ñ¼Ó±¶£¬È»ºóÑ¡Ôñ×î¸ß¼Û¡£Èç¹û×î¸ß¼ÛÉÙÓÚ»òµÈÓÚ $50£¬WHILE Ñ»·ÖØÐÂÆô¶¯²¢Ôٴν«¼Û¸ñ¼Ó±¶¡£¸ÃÑ»·²»¶ÏµØ½«¼Û¸ñ¼Ó±¶Ö±µ½×î¸ß¼Û¸ñ³¬¹ý $50£¬È»ºóÍ˳ö WHILE Ñ»·²¢´òÓ¡Ò»ÌõÏûÏ¢¡£
USE pubs
GO
WHILE (SELECT AVG(price) from titles) < $30
BEGIN
UPDATE titles
SET price = price * 2
SELECT MAX(price) from titles
IF (SELECT MAX(price) from titles) > $50
BREAK
ELSE
CONTINUE
END
PRINT 'Too much for the market to bear'
B. ÔÚ´øÓÐÓαêµÄ¹ý³ÌÖÐʹÓà WHILE
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alter table tableNam ......
set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
go
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@TableName varchar(50), --±íÃû
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