SQL to C: Year-Month Intervals

The identifiers for the year-month interval ODBC SQL data types are the following:

• SQL_INTERVAL_MONTH
• SQL_INTERVAL_YEAR
• SQL_INTERVAL_YEAR_TO_MONTH

The following table shows the ODBC C data types to which year-month interval SQL data may be converted. For an explanation of the columns and terms in the table, see Converting Data from SQL to C Data Types.

C type identifier	Test	TargetValuePtr	StrLen_or_IndPtr	SQLSTATE
SQL_C_INTERVAL_MONTH[a] SQL_C_INTERVAL_YEAR[a] SQL_C_INTERVAL_YEAR_TO_MONTH[a]	Trailing fields portion not truncated Trailing fields portion truncated Leading precision of target is not big enough to hold data from source	Data Truncated data Undefined	Length of data in bytes Length of data in bytes Undefined	n/a 01S07 22015
SQL_C_STINYINT[b] SQL_C_UTINYINT[b] SQL_C_USHORT[b] SQL_C_SHORT[b] SQL_C_SLONG[b] SQL_C_ULONG[b] SQL_C_NUMERIC[b] SQL_C_BIGINT[b]	Interval precision was a single field and the data was converted without truncation Interval precision was a single field and truncated whole Interval precision was not a single field	Data Truncated data Undefined	Size of the C data type Length of data in bytes Size of the C data type	n/a 22003 22015
SQL_C_BINARY	Byte length of data <= BufferLength Byte length of data > BufferLength	Data Undefined	Length of data in bytes Undefined	n/a 22003
SQL_C_CHAR	Character byte length < BufferLength Number of whole (as opposed to fractional) digits < BufferLength Number of whole (as opposed to fractional) digits >= BufferLength	Data Truncated data Undefined	Size of the C data type Size of the C data type Undefined	n/a 01004 22003
SQL_C_WCHAR	Character length < BufferLength Number of whole (as opposed to fractional) digits < BufferLength Number of whole (as opposed to fractional) digits >= BufferLength	Data Truncated data Undefined	Size of the C data type Size of the C data type Undefined	n/a 01004 22003

[a] A year-month interval SQL type can be converted to any year-month interval C type.

[b] If the interval precision is a single field (one of YEAR or MONTH), the interval SQL type can be converted to any exact numeric (SQL_C_STINYINT, SQL_C_UTINYINT, SQL_C_USHORT, SQL_C_SHORT, SQL_C_SLONG, SQL_C_ULONG, or SQL_C_NUMERIC).

Default conversions

The default conversion of an interval SQL type is to the corresponding C interval data type. The application then binds the column or parameter (or sets the SQL_DESC_DATA_PTR field in the appropriate record of the ARD) to point to the initialized SQL_INTERVAL_STRUCT structure (or passes a pointer to the SQL_ INTERVAL_STRUCT structure as the TargetValuePtr argument in a call to SQLGetData).