Approximate Numeric Data Types
| Element | Description | Restrictions | Syntax |
|---|---|---|---|
| float_precision | The float_precision is ignored, but is ANSI/ISO compliant. | Must be a positive integer. Specified value has no effect. | Literal Number |
| precision | Significant digits. Default is 16. | An integer; 1 precision 32 | Literal Number |
Use approximate numeric data types for very large and very small numbers that can tolerate some degree of rounding during arithmetic operations.
| Data Type | Description |
|---|---|
| DEC(p) | Synonym for DECIMAL(p) |
| DECIMAL(p) | Stores floating-point decimal values in the approximate range from 1.0E-130 to 9.99E+126 The p parameter specifies the precision. If no precision is specified, the default is 16. This floating-point data type is available as an approximate numeric type only in a database that is not ANSI-compliant. In an ANSI-compliant database, DECIMAL(p) is implemented as a fixed-point DECIMAL; see Exact Numeric Data Types. |
| DOUBLE PRECISION | ANSI-compliant synonym for FLOAT. The float_precision term is not valid when you use this synonym in data type declarations. |
| FLOAT | Stores double-precision floating-point numbers with up to 16 significant digits. The float-precision parameter is accepted in data-type declarations for compliance with the ANSI/ISO standard for SQL, but this parameter has no effect on the actual precision of values that the database server stores. |
| NUMERIC(p) | ANSI-compliant synonym for DECIMAL(p) In an ANSI-compliant database, this is implemented as an exact numeric type, with the specified precision and a scale of zero, rather than an approximate numeric (floating-point) data type. |
| REAL | ANSI-compliant synonym for SMALLFLOAT |
| SMALLFLOAT | Stores single-precision floating-point numbers with approximately 8 significant digits |
The built-in number data types of Informix® database servers support real numbers. They cannot directly store imaginary or complex numbers.
In Informix®, you must create a user-defined data type for applications that support values that can have an imaginary part.
No more than nine arguments to an external UDR can be DECIMAL data types of SQL that the UDR declares as BigDecimal data types of the Java™ language.