SQL中CAST和CONVERT的区别

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CAST语法：CAST ( expression AS data_type )

CONVERT语法：CONVERT (data_type[(length)], expression [, style])

style格式在转换时间时候的格式如下:

    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 | 100 | mon dd yyyy hh:miAM(或PM)
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1                                |   101    美国                 |    mm/dd/yy
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2                                |   102     ANSI                |    yy-mm-dd
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3 | 103 英法 | dd/mm/yy
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4 | 104 德国 | dd.mm.yy
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5                                |   105     意大利              |    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                                |   109                             |    mon dd yyyy hh:mi:ss:mmmmAM(或PM)
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10                              |   110     美国                  |    mm-dd-yy
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11                              |   111     日本                  |    yy/mm/dd
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12                              |   112     ISO                   |    yymmdd
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13                              |   113      欧洲默认值      |    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                              |   120      ODBC 规范      |     yyyy-mm-dd hh:mi:ss(24小时制)
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21                              |    121                            |     yyyy-mm-dd hh:mi:ss:mmm(24小时制)