C to SQL: Day-Time Intervals

The identifiers for the 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

SQL- STATE

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_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), then 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);