MySQL数据类型转换函数CAST
1、固定值转为BINARY 二进制型
1 2 | SELECT CAST ( 1231 AS BINARY ) AS result
运行结果:1231
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2、int类型值转为CHAR 字符型
1 2 | SELECT CAST (1995 AS CHAR ) as result
运行结果: "1995"
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3、固定时间字符串转为DATE 日期,格式为 'YYYY-MM-DD’
1 2 | SELECT CAST ( '2019-08-29 16:50:21' as date ) as result
运行结果:2019-08-29
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4、固定时间字符串转为DATETIME 日期加具体的时间,格式为 'YYYY-MM-DD HH:MM:SS’
1 2 | SELECT CAST ( '2019-08-29 16:50:21' as DATETIME) as result
运行结果:2019-08-29 16:50:21
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5、固定时间字符串转为TIME 时间,格式为 'HH:MM:SS’
1 2 | SELECT CAST ( '2019-08-29 16:50:21' as TIME ) as result
运行结果:16:50:21
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6、float型值通过DECIMAL 获取精度
1 2 | SELECT CAST (220.23211231 AS DECIMAL (10, 3)) AS result
运行结果:220.232
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7、固定字符串转为SIGNED int 型
1 2 | SELECT CAST ( "12321" AS SIGNED ) AS result
运行结果:12321
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8、固定字符串转为UNSIGNED 无符号int
1 2 | SELECT CAST ( "12321" AS UNSIGNED ) AS result
运行结果:12321
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示例:
1 | and ( CAST (baofeidate AS DATE ) >= '".$date1_search_bf."' and CAST (baofeidate AS DATE ) <= '".$date2_search_bf."' )
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