MDAC 2.5 SDK - ODBC Desktop Database Drivers


 

Paradox Data Types

The ODBC Paradox driver maps Paradox data types to ODBC SQL data types. The following table lists all Paradox data types and shows the ODBC SQL data types they are mapped to.

Paradox data type ODBC data type
ALPHANUMERIC SQL_VARCHAR
AUTOINCREMENT[1] SQL_INTEGER
BCD[1] SQL_DOUBLE
BYTES[1] SQL_BINARY
DATE SQL_DATE
IMAGE[2] SQL_LONGVARBINARY
LOGICAL[1] SQL_BIT
LONG[1] SQL_INTEGER
MEMO[2] SQL_LONGVARCHAR
MONEY[1] SQL_DOUBLE
NUMBER SQL_DOUBLE
SHORT SQL_SMALLINT
TIME[1] SQL_TIMESTAMP
TIMESTAMP[1] SQL_TIMESTAMP

[1]   Valid only for Paradox versions 5.x.

[2]   Valid only for Paradox versions 4.x and 5.x.

Note   SQLGetTypeInfo returns ODBC SQL data types. All conversions in Appendix D of the ODBC Programmer's Reference are supported for the ODBC SQL data types listed earlier in this topic.

The following table shows limitations on Paradox data types.

Data type Description
ALPHANUMERIC Creating an ALPHANUMERIC column of zero or unspecified length actually returns a 255-byte column.
BYTES If you insert NULL into a binary column with the Paradox5 driver, it is changed to 0.
LONG The maximum negative value supported by the Paradox driver for the Long data type in Paradox 5.x is not -2^31 (-2147483648), as it should be since Long maps to the ODBC data type SQL_INTEGER. The maximum negative value supported for Long is actually -2^31 + 1 (-2147483647).
TIMESTAMP When a value is inserted into a TIMESTAMP column by the Paradox driver, then subsequently retrieved from the column, the retrieved value may differ from the inserted value by as much as 1 second because of rounding.

More limitations on data types can be found in Data Type Limitations.