Advanced Oracle PL/SQL Programming with Packages

5.12. PLVfk: Foreign Key Interface

The PLVfk (PL/Vision Foreign Key) package is a high-level, easy-to-use interface to look up foreign key information in your tables. See Chapter 19 for details.

5.12.1. Package Constants

c_prefix CONSTANT VARCHAR2(1) := 'P';

Specifies that the column abbreviation is to be used as a prefix.

c_suffix CONSTANT VARCHAR2(1) := 'S';

Specifies that the column abbreviation is to be used as a suffix.

c_no_change CONSTANT VARCHAR2(10) := 'NO CHANGE';

Used to indicate that no change is to be made to the string value.

c_int_no_change CONSTANT INTEGER := 0;

Used to indicate that no change is to be made to the INTEGER value.

5.12.2. Setting the PLVfk configuration

PROCEDURE set_vclen (length_in IN INTEGER);

Sets the default VARCHAR2 length for the foreign key named retrieved by the PLVfk.name function.

PROCEDURE set_id_default
   (string_in IN VARCHAR2 := c_no_change,
    type_in IN VARCHAR2 := c_no_change);

Sets the default value to be used as the suffix or prefix of the name for the ID column.

PROCEDURE set_nm_default
   (string_in IN VARCHAR2 := c_no_change,
    type_in IN VARCHAR2 := c_no_change);

Sets the default value to be used as the suffix or prefix of the name for the name column.

5.12.3. Looking up the name

FUNCTION name (fk_id_in IN INTEGER, fk_table_in IN VARCHAR2, fk_id_col_in IN VARCHAR2 := c_no_change, fk_nm_col_in IN VARCHAR2 := c_no_change, max_length_in IN INTEGER := c_int_no_change, where_clause_in IN VARCHAR2 := NULL) RETURN VARCHAR2; ...