SQL中CONVERT转化函数的用法
CONVERT的使用方法:
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格式:
CONVERT(data_type,expression[,style])
说明:
此样式一般在时间类型(datetime,smalldatetime)与字符串类型(nchar,nvarchar,char,varchar)
相互转换的时候才用到.
例子:
SELECT CONVERT(varchar(30),getdate(),101) now
结果为
now
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09/15/2001
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style数字在转换时间时的含义如下
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Style(2位表示年份) | Style(4位表示年份) | 输入输出格式
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- | 0 or 100 | mon dd yyyy hh:miAM(或PM)
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1 | 101 | mm/dd/yy
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2 | 102 | yy-mm-dd
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3 | 103 | dd/mm/yy
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4 | 104 | dd-mm-yy
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5 | 105 | dd-mm-yy
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6 | 106 | dd mon yy
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7 | 107 | mon dd,yy
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8 | 108 | hh:mm:ss
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- | 9 or 109 | mon dd yyyy hh:mi:ss:mmmmAM(或PM)
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10 | 110 | mm-dd-yy
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11 | 111 | yy/mm/dd
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12 | 112 | yymmdd
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- | 13 or 113 | dd mon yyyy hh:mi:ss:mmm(24小时制)
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14 | 114 | hh:mi:ss:mmm(24小时制)
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- | 20 or 120 | yyyy-mm-dd hh:mi:ss(24小时制)
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- | 21 or 121 | yyyy-mm-dd hh:mi:ss:mmm(24小时制)
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concat方法的结果等于:result = string1 + string2 + string3 + … + stringN