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c-treeDB API API for C

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Clear the field data and set the field's NULL flag.


CTDBRET ctdbClearField(CTHANDLE Handle, NINT FieldNbr)


ctdbClearField() clears the field data and sets the field's NULL flag.

  • Handle [in] the record handle.
  • FieldNbr [in] the field number.

Note: this function only edits a single field in a single record/row.

Additionally, ctdbClearField() also sets the NULL flag. To clear the NULL flag, write a value to the field in its relevant record, even if it is a zero-length string.


ctdbClearField() returns CTDBRET_OK on success, or c-treeDB API error code on failure.

See also

ctdbClearRecord, ctdbIsNullField

To read/write the "NOT NULL" attribute of a column in the SQL layer, see ctdbGetFieldNullFlag and ctdbSetFieldNullFlag