SQL to C conversion for timestamp data

You can convert the timestamp SQL data type, SQL_TYPE_TIMESTAMP, to a C data type.

The following table shows information about converting timestamp SQL data to C data.

Table 1. Conversion of timestamp SQL data to C data
fCType Test rgbValue pcbValue SQLSTATE
SQL_C_CHAR Display size < cbValueMax Data Data length (in bytes) 000001
19 <= cbValueMax <= Display size Truncated data2 Data length (in bytes) 01004
cbValueMax < 19 Untouched Data length (in bytes) 22003
SQL_C_WCHAR Display size < cbValueMax Data Data length (in bytes) 000001
38 <= cbValueMax <= Display size Truncated data2 Data length (in bytes) 01004
cbValueMax < 38 Untouched Data length (in bytes) 22003
SQL_C_TYPE_DATE None Truncated data3 64 01004
SQL_C_TYPE_TIME None 5 Truncated data6 64 01004
SQL_C_TYPE_TIMESTAMP None 5 Data 164 000001
Fractional seconds portion of timestamp is truncated. 5 Data2 16 01004
SQL_C_TYPE_TIMESTAMP_EXT None 5 Data 20 00000
SQL_C_TYPE_TIMESTAMP_EXT_TZ7 None5 Data 24 00000
Notes:
  1. SQLSTATE 00000 is not returned by SQLGetDiagRec(), rather it is indicated when the function returns SQL_SUCCESS.
  2. The fractional seconds of the timestamp are truncated.
  3. The time portion of the timestamp is deleted.
  4. This is the size of the corresponding C data type.
  5. The value of cbValueMax is ignored for this conversion. The driver assumes that the size of rgbValue is the size of the C data type.
  6. The date portion of the timestamp is deleted.
  7. The time zone fields of the TIMESTAMP_STRUCT_EXT_TZ structure are set based on either CLIENTTIMEZONE, SESSIONTIMEZONE, or the current system time zone of the machine on which the application is running.

When the timestamp SQL data type is converted to the character C data type, the resulting string is in the "yyyy-mm-dd hh:mm:ss[.fff[fff]]” format (regardless of the precision of the timestamp SQL data type).