TINYINT[(M)] [UNSIGNED] [ZEROFILL] A very small integer. The signed range is -128 to 127. The unsigned range is 0 to 255. SMALLINT[(M)] [UNSIGNED] [ZEROFILL] A small integer. The signed range is -32768 to 32767. The unsigned range is 0 to 65535. MEDIUMINT[(M)] [UNSIGNED] [ZEROFILL] A medium-size integer. The signed range is -8388608 to 8388607. The unsigned range is 0 to 16777215. INT[(M)] [UNSIGNED] [ZEROFILL] A normal-size integer. The signed range is -2147483648 to 2147483647. The unsigned range is 0 to 4294967295. INTEGER[(M)] [UNSIGNED] [ZEROFILL] This is a synonym for INT. BIGINT[(M)] [UNSIGNED] [ZEROFILL] A large integer. The signed range is -9223372036854775808 to 9223372036854775807. The unsigned range is 0 to 18446744073709551615. Some things you should be aware about BIGINT columns: As all arithmetic is done using signed BIGINT or DOUBLE values, so you shouldn\'t use unsigned big integers larger than 9223372036854775807 (63 bits) except with bit functions! If you do that, some of the last digits in the result may be wrong because of rounding errors when converting the BIGINT to a DOUBLE. You can always store an exact integer value in a BIGINT column by storing it as a string, as there is in this case there will be no intermediate double representation. `-\', `+\', and `*\' will use BIGINT arithmetic when both arguments are INTEGER values! This means that if you multiply two big integers (or results from functions that return integers) you may get unexpected results when the result is larger than 9223372036854775807. FLOAT(precision) [ZEROFILL] A floating-point number. Cannot be unsigned. precision can be <=24 for a single-precision floating-point number and between 25 and 53 for a double-precision floating-point number. These types are like the FLOAT and DOUBLE types described immediately below. FLOAT(X) has the same range as the corresponding FLOAT and DOUBLE types, but the display size and number of decimals is undefined. In MySQL Version 3.23, this is a true floating-point value. In earlier MySQL versions, FLOAT(precision) always has 2 decimals. Note that using FLOAT may give you some unexpected problems as all calculation in MySQL is done with double precision. See section 20.19 Solving Problems with No Matching Rows. This syntax is provided for ODBC compatibility. FLOAT[(M,D)] [ZEROFILL] A small (single-precision) floating-point number. Cannot be unsigned. Allowable values are -3.402823466E+38 to -1.175494351E-38, 0, and 1.175494351E-38 to 3.402823466E+38. The M is the display width and D is the number of decimals. FLOAT without an argument or with an argument of <= 24 stands for a single-precision floating-point number. DOUBLE[(M,D)] [ZEROFILL] A normal-size (double-precision) floating-point number. Cannot be unsigned. Allowable values are -1.7976931348623157E+308 to -2.2250738585072014E-308, 0, and 2.2250738585072014E-308 to 1.7976931348623157E+308. The M is the display width and D is the number of decimals. DOUBLE without an argument or FLOAT(X) where 25 <= X <= 53 stands for a double-precision floating-point number. DOUBLE PRECISION[(M,D)] [ZEROFILL] REAL[(M,D)] [ZEROFILL] These are synonyms for DOUBLE. DECIMAL[(M[,D])] [ZEROFILL] An unpacked floating-point number. Cannot be unsigned. Behaves like a CHAR column: ``unpacked\'\' means the number is stored as a string, using one character for each digit of the value. The decimal point and, for negative numbers, the `-\' sign, are not counted in M (but space for these are reserved). If D is 0, values will have no decimal point or fractional part. The maximum range of DECIMAL values is the same as for DOUBLE, but the actual range for a given DECIMAL column may be constrained by the choice of M and D. If D is left out it\'s set to 0. If M is left out it\'s set to 10. Note that in MySQL Version 3.22 the M argument had to includes the space needed for the sign and the decimal point. NUMERIC(M,D) [ZEROFILL] This is a synonym for DECIMAL. DATE A date. The supported range is \'1000-01-01\' to \'9999-12-31\'. MySQL displays DATE values in \'YYYY-MM-DD\' format, but allows you to assign values to DATE columns using either strings or numbers. See section 7.3.3.2 The DATETIME, DATE, and TIMESTAMP Types. DATETIME A date and time combination. The supported range is \'1000-01-01 00:00:00\' to \'9999-12-31 23:59:59\'. MySQL displays DATETIME values in \'YYYY-MM-DD HH:MM:SS\' format, but allows you to assign values to DATETIME columns using either strings or numbers. See section 7.3.3.2 The DATETIME, DATE, and TIMESTAMP Types. TIMESTAMP[(M)] A timestamp. The range is \'1970-01-01 00:00:00\' to sometime in the year 2037. MySQL displays TIMESTAMP values in YYYYMMDDHHMMSS, YYMMDDHHMMSS, YYYYMMDD, or YYMMDD format, depending on whether M is 14 (or missing), 12, 8, or 6, but allows you to assign values to TIMESTAMP columns using either strings or numbers. A TIMESTAMP column is useful for recording the date and time of an INSERT or UPDATE operation because it is automatically set to the date and time of the most recent operation if you don\'t give it a value yourself. You can also set it to the current date and time by assigning it a NULL value. See section 7.3.3 Date and Time Types. A TIMESTAMP is always stored in 4 bytes. The M argument only affects how the TIMESTAMP column is displayed. Note that TIMESTAMP(X) columns where X is 8 or 14 are reported to be numbers while other TIMESTAMP(X) columns are reported to be strings. This is just to ensure that one can reliably dump and restore the table with these types! See section 7.3.3.2 The DATETIME, DATE, and TIMESTAMP Types. TIME A time. The range is \'-838:59:59\' to \'838:59:59\'. MySQL displays TIME values in \'HH:MM:SS\' format, but allows you to assign values to TIME columns using either strings or numbers. See section 7.3.3.3 The TIME Type. YEAR[(2|4)] A year in 2- or 4-digit format (default is 4-digit). The allowable values are 1901 to 2155, 0000 in the 4-digit year format, and 1970-2069 if you use the 2-digit format (70-69). MySQL displays YEAR values in YYYY format, but allows you to assign values to YEAR columns using either strings or numbers. (The YEAR type is new in MySQL Version 3.22.). See section 7.3.3.4 The YEAR Type. [NATIONAL] CHAR(M) [BINARY] A fixed-length string that is always right-padded with spaces to the specified length when stored. The range of M is 1 to 255 characters. Trailing spaces are removed when the value is retrieved. CHAR values are sorted and compared in case-insensitive fashion according to the default character set unless the BINARY keyword is given. NATIONAL CHAR (short form NCHAR) is the ANSI SQL way to define that a CHAR column should use the default CHARACTER set. This is the default in MySQL. CHAR is a shorthand for CHARACTER. MySQL allows you to create a column of type CHAR(0). This is mainly useful when you have to be compliant with some old applications that depend on the existence of a column but that do not actually use the value. This is also quite nice when you need a column that only can take 2 values: A CHAR(0), that is not defined as NOT NULL, will only occupy one bit and can only take 2 values: NULL or \"\". See section 7.3.4.1 The CHAR and VARCHAR Types. [NATIONAL] VARCHAR(M) [BINARY] A variable-length string. NOTE: Trailing spaces are removed when the value is stored (this differs from the ANSI SQL specification). The range of M is 1 to 255 characters. VARCHAR values are sorted and compared in case-insensitive fashion unless the BINARY keyword is given. See section 7.7.1 Silent Column Specification Changes. VARCHAR is a shorthand for CHARACTER VARYING. See section 7.3.4.1 The CHAR and VARCHAR Types. TINYBLOB TINYTEXT A BLOB or TEXT column with a maximum length of 255 (2^8 - 1) characters. See section 7.7.1 Silent Column Specification Changes. See section 7.3.4.2 The BLOB and TEXT Types. BLOB TEXT A BLOB or TEXT column with a maximum length of 65535 (2^16 - 1) characters. See section 7.7.1 Silent Column Specification Changes. See section 7.3.4.2 The BLOB and TEXT Types. MEDIUMBLOB MEDIUMTEXT A BLOB or TEXT column with a maximum length of 16777215 (2^24 - 1) characters. See section 7.7.1 Silent Column Specification Changes. See section 7.3.4.2 The BLOB and TEXT Types. LONGBLOB LONGTEXT A BLOB or TEXT column with a maximum length of 4294967295 (2^32 - 1) characters. See section 7.7.1 Silent Column Specification Changes. Note that because the server/client protocol and MyISAM tables has currently a limit of 16M per communication packet / table row, you can\'t yet use this the whole range of this type. See section 7.3.4.2 The BLOB and TEXT Types. ENUM(\'value1\',\'value2\',...) An enumeration. A string object that can have only one value, chosen from the list of values \'value1\', \'value2\', ..., NULL or the special \"\" error value. An ENUM can have a maximum of 65535 distinct values. See section 7.3.4.3 The ENUM Type. SET(\'value1\',\'value2\',...) A set. A string object that can have zero or more values, each of which must be chosen from the list of values \'value1\', \'value2\', ... A SET can have a maximum of 64 members. See section 7.3.4.4 The SET Type.
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