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HomeDatabaseMysql TutorialMySQL字段的取值范围

TINYINT -128 127 TINYINT UNSIGNED 0 255 SMALLINT -32768 32767 SMALLINT UNSIGNED 0 65535 MEDIUMINT -8388608 8388607 MEDIUMINT UNSIGNED 0 16777215 INT 或 INTEGER -2147483648 2147483647 INT UNSIGNED 或 INTEGER UNSIGNED 0 4294967295 BIGINT -92

  TINYINT

  -128 – 127

  TINYINT UNSIGNED

  0 – 255

  SMALLINT

  -32768 – 32767

  SMALLINT UNSIGNED

  0 – 65535

  MEDIUMINT

  -8388608 – 8388607

  MEDIUMINT UNSIGNED

  0 – 16777215

  INT 或 INTEGER

  -2147483648 – 2147483647

  INT UNSIGNED 或 INTEGER UNSIGNED

  0 – 4294967295

  BIGINT

  -9223372036854775808 – 9223372036854775807

  BIGINT UNSIGNED

  0 – 18446744073709551615

  FLOAT

  -3.402823466E+38 – -1.175494351E-38

  0

  1.175494351E-38 – 3.402823466E+38

  DOUBLE 或 DOUBLE PRECISION 或 REAL

  -1.7976931348623157E+308 – -2.2250738585072014E-308

  0

  2.2250738585072014E-308 – 1.7976931348623157E+308

  DECIMAL[(M,[D])] 或 NUMERIC(M,D)

  由M(整个数字的长度,包括小数点,小数点左边的位数,小数点右边的位数,但不包括负号)和D(小数点右边的位数)来决定,M缺省为10,D缺省为0

  DATE

  1000-01-01 – 9999-12-31

  DATETIME

  1000-01-01 00:00:00 – 9999-12-31 23:59:59

  TIMESTAMP

  1970-01-01 00:00:00 – 2037年的某天(具体是哪天我也不知道,呵呵)

  TIME

  -838:59:59′ to 838:59:59

  YEAR[(2|4)]

  缺省为4位格式,4位格式取值范围为1901 – 2155,0000,2位格式取值范围为70-69(1970-2069)

  CHAR(M) [BINARY] 或 NCHAR(M) [BINARY]

  M的范围为1 – 255,如果没有BINARY项,则不分大小写,NCHAR表示使用缺省的字符集.在数据库中以空格补足,但在取出来时末尾的空格将自动去掉.

  [NATIONAL] VARCHAR(M) [BINARY]

  M的范围为1 – 255.在数据库中末尾的空格将自动去掉.

  TINYBLOB 或 TINYTEXT

  255(2^8-1)个字符

  BLOB 或 TEXT

  65535(2^16-1)个字符

  MEDIUMBLOB 或 MEDIUMTEXT

  16777215 (2^24-1)个字符

  LONGBLOB 或 LONGTEXT

  4294967295 (2^32-1)个字符

  ENUM(‘value1′,’value2′,…)

  可以总共有65535个不同的值

  SET(‘value1′,’value2′,…)

 

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