Data stored on a data source has a SQL data type, which may be specific to that data source. A driver maps data source-specific SQL data types to ODBC SQL data types. (A driver returns these mappings through EDSGetTypeInfo. It also uses the ODBC SQL data types to describe the data types of columns and parameters in EDSColAttributes, EDSDescribeCol, and EDSDescribeParam.)

Each ODBC SQL data type corresponds to an ESL data type. Your application can specify the ESL data type with the ETYPE argument in EDSBindCol, EDSGetData, or EDSSetParam. Before returning data from the data source, ESL Database Services (EDS) converts it to the specified ESL data type. Before sending data to the data source, EDS converts it from the specified ESL data type.

This section discusses the following:

•SQL data types

•ESL data types

•Default data type conversions

•Precision, scale, length, and display size of SQL data types

•Converting data from SQL to ESL data types

•Converting data from ESL to SQL data types