用于查询我引用谁，谁引用我的问题 Examples: 查询我引用谁 SELECT*FROMTABLE(FK_UTIL.get_refering_stats(TABLE_A)); 查询谁引用我 SELECT*FROMTABLE(FK_UTIL.get_refered_stats(TABLE_A)); 查询ID为的某条记录的被引用计数 SELECT*FROMTABLE(FK_UTIL.get_re

Examples:

查询我引用谁
SELECT * FROM TABLE(FK_UTIL.get_refering_stats('TABLE_A'));

查询谁引用我
SELECT * FROM TABLE(FK_UTIL.get_refered_stats('TABLE_A'));

查询ID为的某条记录的被引用计数
SELECT * FROM TABLE(FK_UTIL.get_refered_count('TABLE_A', ID));

查询某种条件下的被引用计数
-- 查询code为1的某条记录的被引用计数
SELECT * FROM TABLE(FK_UTIL.get_refered_count_cond('xb_std_types', 'code', '1'));

查询某表在某种条件下的被引用情况，并且附带出更详细的信息
SELECT TABLE_A.id, TABLE_A.COLUMN1, TABLE_A.COLUMN2, ..., stats.child_table, stats.refer_count
FROM TABLE_A
JOIN TABLE(FK_UTIL.get_refered_count_cond('TABLE_A', 'COLUMN', 'VALUE')) stats
ON stats.parent_id=TABLE_A.id;
<无> $velocityCount-->

-- 以下是安装脚本
CREATE OR REPLACE TYPE fk_stats_row AS object (
 child_table varchar2(32),
 child_table_fk_col varchar2(32),
 parent_table varchar2(32),
 parent_table_pk_col varchar2(32)
);
/
 
CREATE OR REPLACE TYPE fk_stats AS TABLE OF fk_stats_row;
/
 
CREATE OR REPLACE TYPE fk_refered_count_row AS object (
 child_table varchar2(32),
 parent_id NUMBER(19),
 refer_count NUMBER(19)
);
/
 
CREATE OR REPLACE TYPE fk_refered_count AS TABLE OF fk_refered_count_row;
/
 
CREATE OR REPLACE TYPE id_array AS TABLE OF NUMBER(19);
/
 
CREATE OR REPLACE package FK_UTIL
IS
 -- 获得我所引用的表
 FUNCTION get_refering_stats(v_table_name varchar2) RETURN fk_stats;
 -- 获得所有子表及外键列
 FUNCTION get_refered_stats(v_table_name varchar2) RETURN fk_stats;
 -- 获得所有子表对某个ID的引用条数
 FUNCTION get_refered_count(v_parent_table varchar2, v_parent_id NUMBER) RETURN fk_refered_count;
 -- 获得所有子表对符合条件的某些记录的引用条数
 FUNCTION get_refered_count_cond(v_parent_table varchar2, v_cond_col varchar2, v_cond varchar2) RETURN fk_refered_count;
END FK_UTIL;
/
 
CREATE OR REPLACE package body FK_UTIL
IS
 -- 获得我所引用的表
 FUNCTION get_refering_stats(v_table_name varchar2) RETURN fk_stats
 IS
 v_ret fk_stats := fk_stats();
 BEGIN
 SELECT CAST(
 multiset(
 SELECT a.TABLE_NAME 从表, a.column_name 外键列, b.TABLE_NAME 主表, b.column_name 被引用列
 FROM (
 SELECT uc.TABLE_NAME, ucc.column_name, uc.r_constraint_name
 FROM user_constraints uc
 JOIN user_cons_columns ucc
 ON uc.constraint_name = ucc.constraint_name
 WHERE uc.constraint_type='R'
 ) a,
 (
 SELECT uc.TABLE_NAME, ucc.column_name, uc.constraint_name
 FROM user_constraints uc
 JOIN user_cons_columns ucc
 ON uc.constraint_name = ucc.constraint_name
 ) b
 WHERE
 a.r_constraint_name = b.constraint_name
 AND a.TABLE_NAME = UPPER(v_table_name)
 ) AS fk_stats
 ) INTO v_ret FROM dual;
 RETURN v_ret;
 END get_refering_stats;
 
 -- 获得所有子表及外键列
 FUNCTION get_refered_stats(v_table_name varchar2) RETURN fk_stats
 IS
 v_ret fk_stats := fk_stats();
 BEGIN
 SELECT CAST(
 multiset(
 SELECT a.TABLE_NAME 从表, a.column_name 外键列, b.TABLE_NAME 主表, b.column_name 被引用列
 FROM (
 SELECT uc.TABLE_NAME, ucc.column_name, uc.r_constraint_name
 FROM user_constraints uc
 JOIN user_cons_columns ucc
 ON uc.constraint_name = ucc.constraint_name
 WHERE uc.constraint_type='R'
 ) a,
 (
 SELECT uc.TABLE_NAME, ucc.column_name, uc.constraint_name
 FROM user_constraints uc
 JOIN user_cons_columns ucc
 ON uc.constraint_name = ucc.constraint_name
 ) b
 WHERE
 a.r_constraint_name = b.constraint_name
 AND b.TABLE_NAME = UPPER(v_table_name)
 ) AS fk_stats
 ) INTO v_ret FROM dual;
 RETURN v_ret;
 END get_refered_stats;
 
 -- 获得所有子表对某个ID的引用条数
 FUNCTION get_refered_count(v_parent_table varchar2, v_parent_id NUMBER) RETURN fk_refered_count
 IS
 v_ret fk_refered_count := fk_refered_count();
 v_count NUMBER := 0;
 v_sql varchar2(2000) := '';
 BEGIN
 FOR v_row IN (SELECT * FROM TABLE(get_refered_stats(v_parent_table))) loop
 v_sql := 'select count(*) from '|| v_row.child_table ||' where ' || v_row.child_table_fk_col || ' = ' || v_parent_id;
 EXECUTE immediate v_sql INTO v_count;
 v_ret.extend(1);
 v_ret(v_ret.COUNT) := fk_refered_count_row(v_row.child_table, v_parent_id, v_count);
 END loop;
 RETURN v_ret;
 END get_refered_count;
 -- 获得所有子表对符合条件的某些记录的引用条数
 FUNCTION get_refered_count_cond(v_parent_table varchar2, v_cond_col varchar2, v_cond varchar2) RETURN fk_refered_count
 IS
 v_ret fk_refered_count := fk_refered_count();
 v_id_array id_array := id_array();
 v_sql varchar2(2000) := '';
 BEGIN
 IF UPPER(v_cond_col) LIKE '%ID' THEN
 v_sql := 'select cast(multiset(select id from ' || v_parent_table || ' where '|| v_cond_col ||'=' || v_cond || ') as id_array) from dual';
 ELSE
 v_sql := 'select cast(multiset(select id from ' || v_parent_table || ' where '|| v_cond_col ||'=''' || v_cond || ''') as id_array) from dual';
 END IF;
 EXECUTE immediate v_sql INTO v_id_array;
 FOR id_row IN (SELECT * FROM TABLE(v_id_array)) loop
 FOR count_row IN (SELECT * FROM TABLE(get_refered_count(v_parent_table, id_row.column_value))) loop
 v_ret.extend(1);
 v_ret(v_ret.COUNT) := fk_refered_count_row(count_row.child_table, count_row.parent_id, count_row.refer_count);
 END loop;
 END loop;
 RETURN v_ret;
 END get_refered_count_cond;
END FK_UTIL;
/