SQL Ñ»·Óï¾ä while ½éÉÜ ÊµÀý ¼ò½é
declare @i int
set @i=1
while @i<30
begin
insert into test (userid) values(@i)
set @i=@i+1
end
---------------
while Ìõ¼þ
begin
Ö´ÐвÙ×÷
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}
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BREAK
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CONTINUE
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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'
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@fieldname nvarchar(50)='*',
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@currentpage int output,--µÚ¼¸Ò³
@orderid nvarchar(50),--Ö÷¼üÅÅÐò
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