Data types

Data types in a meta-schema have the same meaning for every supported database type.

If needed, the data type will be converted to the appropriate target database type when generating a database creation / update script. See the SQL adaptation guides in the Genero Business Development Language User Guide for more information on the use of data types in your database.

Table 1. Common data types
Type Description
BIGINT The BIGINT data type is used for storing very large whole numbers.
BIGSERIAL The BIG SERIAL data type produces automatic integer sequences. BIGSERIAL is based on 64 bit integer sequences.
BOOLEAN The BOOLEAN data type stores a logical value, TRUE or FALSE.
BYTE The BYTE data type stores any type of binary data, such as images or sounds.
CHAR The CHAR data type is a fixed-length character string data type.
DATE The DATE data type stores calendar dates with a Year/Month/Day representation.
DATETIME The DATETIME data type stores date and time data with time units from the year to fractions of a second.
DECIMAL The DECIMAL data type is provided to handle large numeric values with exact decimal storage.
FLOAT The FLOAT data type stores values as double-precision floating-point binary numbers with up to 16 significant digits.
INTEGER The INTEGER data type is used for storing large whole numbers.
SERIAL The SERIAL data type produces automatic integer sequences. SERIAL is based on 32 bit integer sequences.
SMALLFLOAT The SMALLFLOAT data type stores values as single-precision floating-point binary numbers with up to 8 significant digits.
SMALLINT The SMALLINT data type is used for storing small whole numbers.
TEXT The TEXT data type stores large text data.
VARCHAR The VARCHAR data type is a variable-length character string data type, with a maximum size. It is converted to the appropriate target database type when generating database creation / update script.
Table 2. Informix® specific data types
Type Description
INTERVAL The INTERVAL data type stores spans of time as Year/Month or Day/Hour/Minute/Second/Fraction units.
MONEY The MONEY data type is provided to store currency amounts with exact decimal storage.
NCHAR / NVARCHAR IBM® Informix® supports the standard NCHAR and NVARCHAR data types. These types are equivalent to CHAR and VARCHAR (the same character set is used), except that the collation order is locale specific with NCHAR/ NVARCHAR types.
Informix specific types should be avoided when designing databases. A warning is displayed when a column uses an Informix specific type: INT8, INTERVAL, MONEY, NCHAR, NVARCHAR, NVARCHAR2, SERIAL8. To correct this warning convert columns to a common data type:
  • INT8 to BIGINT
  • MONEY to DECIMAL
  • SERIAL8 to BIGSERIAL
  • NCHAR / NVARCHAR / NVARCHAR2 to CHAR / VARCHAR and check the Use national char types option when generating database scripts
  • avoid using INTERVAL
Note: The internal data type is used when generating database creation / update scripts or when working with the Business Application Modeler. However, if you edit a data type in a schema from the extracted database, the generic data type used in the creation of the schema might change the internal data type. For example, a column extracted from an Informix® database of type INT8 will be displayed in the schema as BIGINT. If the you change the type definition in the schema back to BIGINT, the database creation / update scripts will this time create a column of type BIGINT in the Informix® database.