A Data Type Conversion

Oracle maps ODBC data types to supported Oracle data types. When the results of a query are returned, Oracle converts the ODBC data types to Oracle data types.

The tables in this appendix show how Oracle maps ODBC data types to supported Oracle data types when it is retrieving data from a non-Oracle system.

This appendix contains the following table:

Table A-1, "Mapping ODBC Data Types to Oracle Data Types"

A.1 Mapping ODBC Data Types to Oracle Data Types

The Oracle Database Gateway for ODBC maps the data types used in ODBC-compliant data sources to supported Oracle data types. When the results of a query are returned, the Oracle database converts the ODBC data types to Oracle data types. For example, the ODBC data type SQL_TYPE_TIMESTAMP is converted to Oracle's DATE data type.

If a table contains a column whose data type is not supported by Oracle Database Gateway for ODBC, the column information is not returned to the Oracle database.

Table A-1 maps ODBC data types into Oracle data types.

Table A-1 Mapping ODBC Data Types to Oracle Data Types

ODBC	Oracle	Comment
`SQL_BIGINT`	`NUMBER(19,0)`	-
`SQL_BINARY`	`RAW`	-
`SQL_CHAR`	`CHAR`	-
`SQL_DECIMAL(p,s)`	`NUMBER(p,s)`	-
`SQL_DOUBLE`	`FLOAT(53)`	-
`SQL_FLOAT`	`FLOAT(53)`	-
`SQL_INTEGER`	`NUMBER(10)` Note: It is possible under some circumstance for the `INTEGER` ANSI data type to map to `Precision 38`, but it usually maps to `Precision 10`.	-
`SQL_INTERVAL_YEAR`	`INTERVAL_YEAR_TO_MONTH`	-
`SQL_INTERVAL_MONTH`	`INTERVAL_YEAR_TO_MONTH`	-
`SQL_INTERVAL_YEAR_TO_MONTH`	`INTERVAL_YEAR_TO_MONTH`	-
`SQL_INTERVAL_DAY`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_HOUR`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_MINUTE`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_SECOND`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_DAY_TO_HOUR`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_DAY_TO_MINUTE`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_DAY_TO_SECOND`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_HOUR_TO_MINUTE`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_HOUR_TO_SECOND`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_INTERVAL_MINUTE_TO_SECOND`	`INTERVAL_DAY_TO_SECOND`	-
`SQL_LONGVARBINARY`	`LONG RAW`	-
`SQL_LONGVARCHAR`	`LONG` Note: If an ANSI SQL implementation defines a large value for the maximum length of `VARCHAR` data, it is possible that ANSI `VARCHAR` will map to `SQL_LONGVARCHAR` and Oracle `LONG`.	-
`SQL_NUMERIC(p[,s])`	`NUMBER(p[,s])`	-
`SQL_REAL`	`FLOAT(24)`	-
`SQL_SMALLINT`	`NUMBER(5)`	-
`SQL_TYPE_TIME`	`CHAR(15)`	-
`SQL_TINYINT`	`NUMBER(3)`	-
`SQL_TYPE_DATE`	`DATE`	-
`SQL_TYPE_TIMESTAMP`	`DATE`	-
`SQL_VARBINARY`	`RAW`	-
`SQL_VARCHAR`	`VARCHAR2`	-
`SQL_WCHAR`	`NCHAR`	-
`SQL_WVARCHAR`	`NVARCHAR`	-
`SQL_WLONGVARCHAR`	`LONG`	if Oracle DB Character Set = Unicode. Otherwise, it is not supported
`SQL_BIT`	`NUMBER(3)`	-