GdaDictConstraint

GdaDictConstraint — Represents a constraint within a database

Synopsis




                    GdaDictConstraint;
enum                GdaDictConstraintType;
enum                GdaDictConstraintFkAction;
GdaDictConstraint*  gda_dict_constraint_new             (GdaDictTable *table,
                                                         GdaDictConstraintType type);
GdaDictConstraint*  gda_dict_constraint_new_with_db     (GdaDictDatabase *db);
GdaDictConstraintType gda_dict_constraint_get_constraint_type
                                                        (GdaDictConstraint *cstr);
gboolean            gda_dict_constraint_equal           (GdaDictConstraint *cstr1,
                                                         GdaDictConstraint *cstr2);
GdaDictTable*       gda_dict_constraint_get_table       (GdaDictConstraint *cstr);
gboolean            gda_dict_constraint_uses_field      (GdaDictConstraint *cstr,
                                                         GdaDictField *field);
void                gda_dict_constraint_pkey_set_fields (GdaDictConstraint *cstr,
                                                         const GSList *fields);
GSList*             gda_dict_constraint_pkey_get_fields (GdaDictConstraint *cstr);
void                gda_dict_constraint_fkey_set_fields (GdaDictConstraint *cstr,
                                                         const GSList *pairs);
GdaDictTable*       gda_dict_constraint_fkey_get_ref_table
                                                        (GdaDictConstraint *cstr);
GSList*             gda_dict_constraint_fkey_get_fields (GdaDictConstraint *cstr);
void                gda_dict_constraint_fkey_set_actions
                                                        (GdaDictConstraint *cstr,
                                                         GdaDictConstraintFkAction on_update,
                                                         GdaDictConstraintFkAction on_delete);
void                gda_dict_constraint_fkey_get_actions
                                                        (GdaDictConstraint *cstr,
                                                         GdaDictConstraintFkAction *on_update,
                                                         GdaDictConstraintFkAction *on_delete);
void                gda_dict_constraint_unique_set_fields
                                                        (GdaDictConstraint *cstr,
                                                         const GSList *fields);
GSList*             gda_dict_constraint_unique_get_fields
                                                        (GdaDictConstraint *cstr);
void                gda_dict_constraint_not_null_set_field
                                                        (GdaDictConstraint *cstr,
                                                         GdaDictField *field);
GdaDictField*       gda_dict_constraint_not_null_get_field
                                                        (GdaDictConstraint *cstr);

Object Hierarchy


  GObject
   +----GdaObject
         +----GdaDictConstraint

Implemented Interfaces

GdaDictConstraint implements GdaXmlStorage and GdaReferer.

Properties


  "user-constraint"          gboolean              : Read / Write

Description

Any type of constraint in a database is represented by one instance of the class (see the possible types of constraints). As some constraints may not depend exclusively on a table, all the constraints are attached to the database itself.

It implements the GdaXmlStorage and GdaReferer interfaces.

Details

GdaDictConstraint

typedef struct _GdaDictConstraint GdaDictConstraint;


enum GdaDictConstraintType

typedef enum
{
	CONSTRAINT_PRIMARY_KEY,
	CONSTRAINT_FOREIGN_KEY,
	CONSTRAINT_UNIQUE,
	CONSTRAINT_NOT_NULL,
	CONSTRAINT_CHECK_EXPR,
	CONSTRAINT_CHECK_IN_LIST,
	CONSTRAINT_CHECK_SETOF_LIST,
	CONSTRAINT_UNKNOWN
} GdaDictConstraintType;


enum GdaDictConstraintFkAction

typedef enum
{
	CONSTRAINT_FK_ACTION_CASCADE,
	CONSTRAINT_FK_ACTION_SET_NULL,
	CONSTRAINT_FK_ACTION_SET_DEFAULT,
	CONSTRAINT_FK_ACTION_SET_VALUE,
	CONSTRAINT_FK_ACTION_NO_ACTION
} GdaDictConstraintFkAction;


gda_dict_constraint_new ()

GdaDictConstraint*  gda_dict_constraint_new             (GdaDictTable *table,
                                                         GdaDictConstraintType type);

Creates a new GdaDictConstraint object

table : the GdaDictTable to which the constraint is attached
type : the type of constraint
Returns : the new object

gda_dict_constraint_new_with_db ()

GdaDictConstraint*  gda_dict_constraint_new_with_db     (GdaDictDatabase *db);

Creates a new GdaDictConstraint object without specifying anything about the constraint except the database it is attached to. This is usefull only when the object is going to be loaded from an XML node.

db : a GdaDictDatabase object
Returns : the new uninitialized object

gda_dict_constraint_get_constraint_type ()

GdaDictConstraintType gda_dict_constraint_get_constraint_type
                                                        (GdaDictConstraint *cstr);

Get the type of constraint the cstr object represents

cstr : a GdaDictConstraint object
Returns : the constraint type

gda_dict_constraint_equal ()

gboolean            gda_dict_constraint_equal           (GdaDictConstraint *cstr1,
                                                         GdaDictConstraint *cstr2);

Compares two GdaDictConstraint objects to see if they are equal, without taking into account the name of the constraints or weather they are user or system defined

cstr1 : the first GdaDictConstraint to compare
cstr2 : the second GdaDictConstraint to compare
Returns : TRUE if the two constraints are equal and FALSE otherwise

gda_dict_constraint_get_table ()

GdaDictTable*       gda_dict_constraint_get_table       (GdaDictConstraint *cstr);

Get the table to which the constraint is attached

cstr : a GdaDictConstraint object
Returns : the GdaDictTable

gda_dict_constraint_uses_field ()

gboolean            gda_dict_constraint_uses_field      (GdaDictConstraint *cstr,
                                                         GdaDictField *field);

Tests if field is part of the cstr constraint

cstr : a GdaDictConstraint object
field : a GdaDictField object
Returns : TRUE if cstr uses field

gda_dict_constraint_pkey_set_fields ()

void                gda_dict_constraint_pkey_set_fields (GdaDictConstraint *cstr,
                                                         const GSList *fields);

Sets the fields which make the primary key represented by cstr. All the fields must belong to the same GdaDictTable to which the constraint is attached

cstr : a GdaDictConstraint object
fields : a list of GdaDictField objects

gda_dict_constraint_pkey_get_fields ()

GSList*             gda_dict_constraint_pkey_get_fields (GdaDictConstraint *cstr);

Get the list of fields composing the primary key constraint which cstr represents. The returned list is allocated and must be de-allocated by the caller.

cstr : a GdaDictConstraint object
Returns : a new list of fields

gda_dict_constraint_fkey_set_fields ()

void                gda_dict_constraint_fkey_set_fields (GdaDictConstraint *cstr,
                                                         const GSList *pairs);

Sets the field pairs which make the foreign key represented by cstr. All the field pairs must list a field which belong to the same GdaDictTable to which the constraint is attached and a field which belongs to a GdaDictTable which is different from the one just mentionned and which is within the same database. The pairs are of type GdaDictConstraintFkeyPair.

cstr : a GdaDictConstraint object
pairs : a list of GdaDictField objects

gda_dict_constraint_fkey_get_ref_table ()

GdaDictTable*       gda_dict_constraint_fkey_get_ref_table
                                                        (GdaDictConstraint *cstr);

Get the GdaDictTable at the other end of the foreign key relation represented by this constraint

cstr : a GdaDictConstraint object
Returns : the GdaDictTable

gda_dict_constraint_fkey_get_fields ()

GSList*             gda_dict_constraint_fkey_get_fields (GdaDictConstraint *cstr);

Get the list of field pairs composing the foreign key constraint which cstr represents. In the returned list, each pair item is allocated and it's up to the caller to free the list and each pair, and the reference count for each pointer to GObjects in each pair is NOT INCREASED, which means the caller of this function DOES NOT hold any reference on the mentionned GObjects (if he needs to, it has to call g_object_ref())

cstr : a GdaDictConstraint object
Returns : a new list of GdaDictConstraintFkeyPair pairs

gda_dict_constraint_fkey_set_actions ()

void                gda_dict_constraint_fkey_set_actions
                                                        (GdaDictConstraint *cstr,
                                                         GdaDictConstraintFkAction on_update,
                                                         GdaDictConstraintFkAction on_delete);

Sets the actions undertaken by the DBMS when some actions occur on the referenced data

cstr : a GdaDictConstraint object
on_update : the action undertaken when an UPDATE occurs
on_delete : the action undertaken when a DELETE occurs

gda_dict_constraint_fkey_get_actions ()

void                gda_dict_constraint_fkey_get_actions
                                                        (GdaDictConstraint *cstr,
                                                         GdaDictConstraintFkAction *on_update,
                                                         GdaDictConstraintFkAction *on_delete);

Get the actions undertaken by the DBMS when some actions occur on the referenced data

cstr : a GdaDictConstraint object
on_update : an address to store the action undertaken when an UPDATE occurs
on_delete : an address to store the action undertaken when a DELETE occurs

gda_dict_constraint_unique_set_fields ()

void                gda_dict_constraint_unique_set_fields
                                                        (GdaDictConstraint *cstr,
                                                         const GSList *fields);

cstr : a GdaDictConstraint object
fields :

gda_dict_constraint_unique_get_fields ()

GSList*             gda_dict_constraint_unique_get_fields
                                                        (GdaDictConstraint *cstr);

Get the list of fields represented by this UNIQUE constraint. It's up to the caller to free the list.

cstr : a GdaDictConstraint object
Returns : a new list of fields

gda_dict_constraint_not_null_set_field ()

void                gda_dict_constraint_not_null_set_field
                                                        (GdaDictConstraint *cstr,
                                                         GdaDictField *field);

cstr :
field :

gda_dict_constraint_not_null_get_field ()

GdaDictField*       gda_dict_constraint_not_null_get_field
                                                        (GdaDictConstraint *cstr);

cstr :
Returns :

Property Details

The "user-constraint" property

  "user-constraint"          gboolean              : Read / Write

Default value: FALSE