Informix Database Data Type

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Data Types supported by INFORMIX
Numeric type
Integer smallint, INTEGER
FLOAT, SMALLFLOAT, DECIMAL (p, s)
Character CHAR (n), VARCHAR (m, r)
Time/DATE type DATE, DATETIME, INTERVAL
Sequential SERIAL
Currency type MONEY
Multimedia TEXT, BYTE

Integer
INTEGER
The INTEGER type stores integers in the range of-2147483647,2147483647)
Storage space: 4 bytes
Synonymous name: INT
SMALLINT
SMALLINT type stores integers in the range of (-32767,327 67)
Storage space: 2 bytes

Floating Point Type
FLOAT (n)
FLOAT (n) Stores double-precision floating-point numbers. The maximum number of valid digits is 16.
FLOAT (n) is equivalent to DOUBLE in C.
Storage space: 8 bytes
Synonymous name: DOUBLE PRECISION
SMALLFLOAT
SMALLFLOAT stores Single-precision floating-point numbers, with a maximum of 8 Valid digits
The SMALLFLOAT type is equivalent to the C language FLOAT type.
Storage space: 4 bytes
Synonymous name: REAL
DECIMAL (p, s)
It is an internal decimal floating point type and has nothing to do with the machine. The maximum number of valid digits is 32.
Value Range: 10 ** (-128) ---- 10 ** (127)
P indicates the precision, and s indicates the number of decimal places.
If p is omitted, it is equivalent to DECIMAL (16)
Storage space: p/2 + 1 byte
Synonymous name: NUMERIC, DEC

Character Type
CHAR (n)
CHAR character type stores characters or strings (fixed length)
N indicates the number of characters. The default value is 1. The value range is 1. The storage space is n characters.
Synonymous name: CHARACTER
VARCHAR (m, r)
The VARCHAR type is used to store variable-length strings.
M indicates the maximum number of characters that can be stored. mr indicates the minimum reserved space (number of bytes). If omitted, the value is zero.
Storage space: the actual string length, which consists of a maximum of m bytes and a minimum of r bytes.
Date type
DATE
DATE indicates the DATE.
The DATE type is represented by an INTEGER internally.
The number of days from to a certain date on January 1, January 1, 1900
Output Format: mm/dd/yy (month/day/year) is related to the Environment Variable DBDATE.
Storage space: 4 bytes
DATETIME
DATETIME stores the date and time at a certain time.
The value range is from year to second.
DATETIME precision Modifier
Year month day -- YEAR MONTH DAY
Hour minute second -- HOUR, MINUTE, and SECOND
FRACTION -- fractional part, less than seconds
Output Format: yyyy-mm-dd hh: mm: ss. ff (yyyy-mm-dd hh: mm: ss. ff ..)
Example: 14:13:56. 324
Description: A column is of the DATETIME type.
Format: column 'datetime' maximum modifier TO minimum Modifier
Example: c1 DATETIME YEAR TO DAY
C2 DATETIME MONTH TO MONTH
C3 datetime year to fraction (3)
Storage space
Number of numbers required for output in each field
YEAR: 4 digits
FRACTION: 5 digits
Other domains: 2 numbers
Bucket: The sum of the numbers of all fields/2 + 1 byte
For example, the DATETIME type of year to day must be
(4 + 2 + 2)/2 + 1 = 5 bytes

The interval type indicates the time span value.

Sequential type
The SERIAL type is a sequence type. The value can be automatically generated by the DBMS when a new record is inserted. If all the values are generated by the DBMS, no duplicates can be ensured.
A table can only have one column of the SERIAL type.
The SERIAL type is an integer and the maximum value is 2147483647 (2G-1)
N indicates the initial value. The default value is 1.
Storage space: 4 bytes.
The SERIAL type is generally used for primary keys.
Currency type
The MONEY type is currency type, which is represented by DECIMAL (p, s) internally.
P indicates the precision. s indicates the number of decimal places, which can be omitted and:
MONEY (p) = MONEY (p, 2) MONEY = MONEY (16, 2)
The MONEY type is displayed with a currency character.
The currency identifier is specified by the DBMONEY environment variable. The default value is the dollar identifier $

Multimedia
The text type is text type, with a maximum of 2 31 to the power bytes.

The byte type is binary data, up to 31 bytes of 2