Constraint functions

Functions
int	RDB_create_constraint (const char *name, RDB_expression *exp, RDB_exec_context *ecp, RDB_transaction *txp)
int	RDB_drop_constraint (const char *name, RDB_exec_context *ecp, RDB_transaction *txp)

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Function Documentation

int RDB_create_constraint	(	const char *	name,
		RDB_expression *	exp,
		RDB_exec_context *	ecp,
		RDB_transaction *	txp
	)

RDB_create_constraint creates a constraint with the name name on the database the transaction specified by txp interacts with.

Returns:

RDB_OK on success, RDB_ERROR if an error occurred.

Errors:

no_running_tx_error

txp does not point to a running transaction.

type_mismatch_error

The *constrp is not of type BOOLEAN.

predicate_violation_error

The *constrp does not evaluate to TRUE.

The call may also fail for a system error, in which case the transaction may be implicitly rolled back.

int RDB_drop_constraint	(	const char *	name,
		RDB_exec_context *	ecp,
		RDB_transaction *	txp
	)

RDB_drop_constraint deletes the constraint with the name name.

Returns:

RDB_OK on success, RDB_ERROR if an error occurred.

Errors:

no_running_tx_error

txp does not point to a running transaction.

not_found_error

A constraint with the name name could not be found.

The call may also fail for a system error, in which case the transaction may be implicitly rolled back.