postgresql - 需要使用 plpgsql 函数截断表

Question

我已经编写了一个 pl/pgsql 函数来截断表。 HIST_CLEANUP_TBL 中有 5 个 table_name。数据库中不存在 5 个表名中的 1 个。

需要的是:它必须检查所有表。如果表不存在，则将错误写入错误表并截断剩余的表。

但是，在这里，只要循环中出现不可用的表，函数就会终止。

如何捕获变量中的错误代码和文本以及如何在不存在1个表的情况下继续循环。

我们正在使用 postgresql 8.2

BEGIN  

    for recordvar in 
    SELECT 'truncate table  ' || TABLE_NAME  as SQRY  FROM HIST_CLEANUP_TBL
    loop
       QUERY1 := recordvar.SQRY;
       RAISE NOTICE 'QUERY: (%)', QUERY1;     

       BEGIN
       execute QUERY1;
       RAISE NOTICE 'QUERY EXECUTED SUCCESSFULLY';   
       EXCEPTION
       WHEN others
       THEN
       --GET STACKED DIAGNOSTICS 
      ERR_NUM := SQLSTATE;
      ERR_MESG := SQLERRM ;

       RAISE NOTICE 'ERROR WHILE EXECUTING THE QUERY : %',ERR_NUM;

      insert into Refresh_Error_tbl(sqlerr_code,sqlerr_desc,sql_desc, INSERT_DT,refresh_load_id) values(ERR_NUM,ERR_MESG,QUERY1,current_timestamp,'1');
       END;
      end loop; 
END;

Answer 1

错误的原因一定是在别的地方。以下代码工作正常:

CREATE TABLE hist_cleanup (
    table_name  text
);

CREATE TABLE table_a();
CREATE TABLE table_b();
--  table_c missing
CREATE TABLE table_d();
CREATE TABLE table_e();

INSERT INTO hist_cleanup
VALUES
    ('table_a')
,   ('table_b')
,   ('table_c')
,   ('table_d')
,   ('table_e');

CREATE TABLE refresh_error (
    sqlerr_code     text
,   sqlerr_desc     text
,   sql_desc        text
,   insert_dt       timestamp
,   refresh_load_id int
);

CREATE OR REPLACE FUNCTION cleanup()
RETURNS VOID AS $$
DECLARE
    _rec    record;
    _query  text;
BEGIN  

    FOR _rec IN (
        SELECT  table_name
        FROM    hist_cleanup
    ) LOOP
        _query := 'TRUNCATE TABLE ' || _rec.table_name;

        RAISE NOTICE 'QUERY: (%)', _query;     

        BEGIN
            EXECUTE _query;
            RAISE NOTICE 'QUERY EXECUTED SUCCESSFULLY';   
        EXCEPTION
            WHEN OTHERS
            THEN
                RAISE NOTICE 'ERROR WHILE EXECUTING THE QUERY: % %', SQLSTATE, SQLERRM;
                INSERT INTO refresh_error (
                    sqlerr_code
                ,   sqlerr_desc
                ,   sql_desc
                ,   insert_dt
                ,   refresh_load_id )
                VALUES (
                    SQLSTATE
                ,   SQLERRM
                ,   _query
                ,   CURRENT_TIMESTAMP
                ,   '1'
                );
        END;
    END LOOP;

    RETURN;

END $$ LANGUAGE plpgsql;

SELECT  cleanup();

输出:

NOTICE:  QUERY: (TRUNCATE TABLE table_a)
NOTICE:  QUERY EXECUTED SUCCESSFULLY
NOTICE:  QUERY: (TRUNCATE TABLE table_b)
NOTICE:  QUERY EXECUTED SUCCESSFULLY
NOTICE:  QUERY: (TRUNCATE TABLE table_c)
NOTICE:  ERROR WHILE EXECUTING THE QUERY: 42P01 relation "table_c" does not exist
NOTICE:  QUERY: (TRUNCATE TABLE table_d)
NOTICE:  QUERY EXECUTED SUCCESSFULLY
NOTICE:  QUERY: (TRUNCATE TABLE table_e)
NOTICE:  QUERY EXECUTED SUCCESSFULLY