C to SQL: Day-Time Intervals

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The identifiers for the day-time interval ODBC C data types are:

SQL_C_INTERVAL_DAY

SQL_C_INTERVAL_HOUR

SQL_C_INTERVAL_MINUTE

SQL_C_INTERVAL_SECOND

SQL_C_INTERVAL_DAY_TO_HOUR

SQL_C_INTERVAL_DAY_TO_MINUTE

SQL_C_INTERVAL_DAY_TO_SECOND

SQL_C_INTERVAL_HOUR_TO_MINUTE

SQL_C_INTERVAL_HOUR_TO_SECOND

SQL_C_INTERVAL_MINUTE_TO_SECOND

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

SQL type identifier Test SQLSTATE
SQL_CHAR[a]

SQL_VARCHAR[a]

SQL_LONGVARCHAR[a]		 Column byte length >= Character byte length

Column byte length < Character byte length[a]

Data value is not a valid interval literal		 n/a

22001

22015
SQL_WCHAR[a]

SQL_WVARCHAR[a]

SQL_WLONGVARCHAR[a]		 Column character length >= Character length of data

Column character length < Character length of data[a]

Data value is not a valid interval literal		 n/a

22001

22015
SQL_TINYINT[b]

SQL_SMALLINT[b] SQL_INTEGER[b]

SQL_BIGINT[b] SQL_NUMERIC[b]

SQL_DECIMAL[b]		 Conversion of a single-field interval did not result in truncation of whole digits

Conversion resulted in truncation of whole digits		 n/a

22003
SQL_INTERVAL_DAY

SQL_INTERVAL_HOUR

SQL_INTERVAL_MINUTE

SQL_INTERVAL_SECOND

SQL_INTERVAL_DAY_TO_HOUR

SQL_INTERVAL_DAY_TO_MINUTE

SQL_INTERVAL_DAY_TO_SECOND

SQL_INTERVAL_HOUR_TO_MINUTE

SQL_INTERVAL_HOUR_TO_SECOND

SQL_INTERVAL_MINUTE_TO_SECOND		 Data value was converted without truncation of any fields

One or more fields of data value were truncated during conversion		 n/a

22015

[a] All C interval data types can be converted to a character data type.

[b] If the type field in the interval structure is such that the interval is a single field (SQL_DAY, SQL_HOUR, SQL_MINUTE, or SQL_SECOND), the interval C type can be converted to any exact numeric (SQL_TINYINT, SQL_SMALLINT, SQL_INTEGER, SQL_BIGINT, SQL_DECIMAL, or SQL_NUMERIC).

The default conversion of an interval C type is to the corresponding day-time interval SQL type.

The driver ignores the length/indicator value when converting data from the interval C data type and assumes that the size of the data buffer is the size of the interval C data type. The length/indicator value is passed in the StrLen_or_Ind argument in SQLPutData and in the buffer specified with the StrLen_or_IndPtr argument in SQLBindParameter. The data buffer is specified with the DataPtr argument in SQLPutData and the ParameterValuePtr argument in SQLBindParameter.

The following example demonstrates how to send interval C data stored in the SQL_INTERVAL_STRUCT structure into a database column. The interval structure contains a DAY_TO_SECOND interval; it will be stored in a database column of type SQL_INTERVAL_DAY_TO_MINUTE.

SQL_INTERVAL_STRUCT is;  
SQLINTEGER cbValue;  
  
// Initialize the interval struct to contain the DAY_TO_SECOND  
// interval "154 days, 22 hours, 44 minutes, and 10 seconds"  
is.intval.day_second.day      = 154;  
is.intval.day_second.hour     = 22;  
is.intval.day_second.minute   = 44;  
is.intval.day_second.second   = 10;  
is.interval_sign              = SQL_FALSE;  
  
// Bind the dynamic parameter  
SQLBindParameter(hstmt, 1, SQL_PARAM_INPUT, SQL_C_INTERVAL_DAY_TO_SECOND,  
                  SQL_INTERVAL_DAY_TO_MINUTE, 0, 0, &is,  
                  sizeof(SQL_INTERVAL_STRUCT), &cbValue);  
  
// Execute an insert statement; "interval_column" is a column  
// whose data type is SQL_INTERVAL_DAY_TO_MINUTE.  
SQLExecDirect(hstmt,"INSERT INTO table(interval_column) VALUES (?)",SQL_NTS);