Data Type Mapping Between Informix and JDBC Data Types

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Data Type Mapping Between Informix and JDBC Data Types

Because there are variations between the SQL data types supported by each database vendor, the JDBC API defines a set of generic SQL data types in the class java.sql.Types. Use these JDBC API data types to reference generic SQL types in your Java programs that use the JDBC API to connect to Informix databases.

The following table shows the Informix data type to which each JDBC API data type maps.

JDBC API Data Type: Informix Data Type
BIGINT: INT8
BINARY: BYTE
BIT ¹: BOOLEAN
REF: Not supported
CHAR: CHAR(n)
DATE: DATE
DECIMAL: DECIMAL
DOUBLE: FLOAT
FLOAT: FLOAT²
INTEGER: INTEGER
LONGVARBINARY: BYTE or BLOB
LONGVARCHAR: TEXT or CLOB
NUMERIC: DECIMAL
NUMERIC: MONEY
REAL: SMALLFLOAT
SMALLINT: SMALLINT
TIME: DATETIME HOUR TO SECOND²
TIMESTAMP: DATETIME YEAR TO FRACTION(5)³
TINYINT: SMALLINT
VARBINARY: BYTE
VARCHAR: VARCHAR(m,r)
BOOLEAN: BOOLEAN
SMALLINT: SMALLINT

¹With Java 1.3.1, the JDBC 3.0 features are undefined. So if you are running Java 1.3.1, then the JDBC type java.sql.Types.OTHER will still map to BOOLEAN. If Java 1.4 is used, java.sql.Types.BOOLEAN maps to BOOLEAN.

² This mapping is JDBC compliant. You can map the JDBC FLOAT data type to the Informix SMALLFLOAT data type for backward compatibility by setting the IFX_SET_FLOAT_AS_SMFLOAT environment variable to 1.

³ Informix DATETIME types are very restrictive and are not interchangeable. For more information, see Field Lengths and Date-Time Data.