How to delete row by row comparing to first collumn?

Question

Hello!
I have a problem - I need to delete row by row , but the problem is, that I know that first COLUMN of any table is a PK.
To retrieve COLUMN NAME I use:
SELECT column_name, table_name FROM USER_TAB_COLUMNS WHERE column_id = 1 and table_name = c1.tmp_table_name;
But this somehow doesn't work.
Below you can see my script (not worked for now):
declare
xxx varchar2(100);
begin
for c1 in (select table_name, tmp_table_name from tmp_tables) loop
EXECUTE IMMEDIATE
' SELECT column_name into '|| xxx ||' FROM USER_TAB_COLUMNS WHERE column_id = 1 and table_name = ' ||''''||c1.tmp_table_name||'''';
execute immediate
'begin
for c2 in (select * from '|| c1.tmp_table_name || ') loop begin
insert into '|| c1.table_name || ' values c2; delete from '|| c1.tmp_table_name || ' where ' || xxx ||' = c2.'||xxx ||'; exception when others then null; end; end loop; end;';
end loop;
end;
P.S. Inserts work perfect. I have a problem with delete rows that are in c1.table_name, from c1.tmp_table_name (this two tables have the same structure, PK, always), because I have different column names in another tables tables that are PK. (for example: K, ID, NS and so on) please help me to write correct script.
For example for first fetched row it will be like:
begin
for c1 in (select table_name, tmp_table_name from tmp_tables) loop
execute immediate
'begin for c2 in (select * from '|| c1.tmp_table_name || ') loop begin
insert into '|| c1.table_name || ' values c2; delete from '|| c1.tmp_table_name ||' where K = c2.K; exception when others then null; end; end loop; end;';
end loop;
end;
That script works perfect. But I have many others tables with different PK - not K.

Answer 1

Solution with error-logging table
-- create the error-logging table
CREATE TABLE tbl_MergeErrors (
    Stamp       TIMESTAMP(3),
    TableName   VARCHAR2(30),
    KeyColumn   VARCHAR2(30),
    KeyValue    VARCHAR2(4000),
    ErrorCode   NUMBER(5),
    ErrorMsg    VARCHAR2(4000),
  CONSTRAINT pk_MergeErrors
      PRIMARY KEY (TableName, Stamp)
      USING INDEX
-- procedure to insert errors
CREATE OR REPLACE
PROCEDURE LogMergeError (pTableName  IN VARCHAR2,
                         pKeyColumn  IN VARCHAR2,
                         pKeyValue   IN VARCHAR2)
IS PRAGMA AUTONOMOUS_TRANSACTION;
    -- you couldn't insert SQLCODE or SQLERRM directly into a table (ORA-00984)
    nSQLCODE   NUMBER(5)      := SQLCODE;
    vcSQLERRM  VARCHAR2(4000) := SQLERRM;
BEGIN
  INSERT INTO tbl_MergeErrors
         (Stamp, TableName, KeyColumn, KeyValue, ErrorCode, ErrorMsg)
      VALUES (SYSTIMESTAMP, RTrim( SubStr( pTableName, 1, 30)),
              RTrim( SubStr( pKeyColumn, 1, 30)), SubStr( pKeyValue, 1, 4000),
              nSQLCODE, vcSQLERRM);
  COMMIT WORK;
-- if an error occured here, then just roll back the autonomous transaction
EXCEPTION
  WHEN OTHERS THEN   ROLLBACK WORK;
END LogMergeError;
-- create the tables and insert test-data
CREATE TABLE TMP_TABLES (
    TABLE_NAME       VARCHAR2(200),
    TMP_TABLE_NAME   VARCHAR2(200),
  CONSTRAINT TMP_TABLES_X PRIMARY KEY (TABLE_NAME)
CREATE TABLE TMP_KL002 (
    K   VARCHAR2(40),
    N   VARCHAR2(200)
CREATE TABLE TMP_TABLE1 (
    NS   VARCHAR2(40),
    N    VARCHAR2(200)
CREATE TABLE KL002 (
    K VARCHAR2(40),
    N VARCHAR2(200),
  CONSTRAINT PK_KL002 PRIMARY KEY (K)
CREATE TABLE TABLE1 (
    NS   VARCHAR2(40),
    N    VARCHAR2(200),
  CONSTRAINT PK_TABLE1 PRIMARY KEY (NS)
INSERT INTO TMP_TABLES (TABLE_NAME, TMP_TABLE_NAME) VALUES ('kl002','tmp_kl002');
INSERT INTO TMP_TABLES (TABLE_NAME, TMP_TABLE_NAME) VALUES ('table1','tmp_table1');
INSERT INTO tmp_KL002 (K, N) VALUES ('00', 'none');
INSERT INTO tmp_KL002 (K, N) VALUES ('07', 'exists');
INSERT INTO tmp_KL002 (K, N) VALUES ('08', 'not assigned');
INSERT INTO tmp_table1 (NS, N) VALUES ('2000', 'basic');
INSERT INTO tmp_table1 (NS, N) VALUES ('3000', 'advanced');
INSERT INTO tmp_table1 (NS, N) VALUES ('4000', 'custom');
COMMIT WORK;
-- to test, if it works correct when primary key values exists before
INSERT INTO KL002 VALUES ('07', 'exists before');
COMMIT WORK;
-- check the data before execution
SELECT * FROM TMP_KL002 ORDER BY K;
SELECT * FROM KL002 ORDER BY K;
SELECT * FROM TMP_TABLE1 ORDER BY NS;
SELECT * FROM TABLE1 ORDER BY NS;
-- empty the error-logging table
TRUNCATE TABLE tbl_MergeErrors DROP STORAGE;
-- a solution
DECLARE
    PLSQL_BLOCK  CONSTANT VARCHAR2(256) := '
BEGIN
  FOR rec IN (SELECT * FROM <0>) LOOP
    BEGIN
      INSERT INTO <1> VALUES rec;
      DELETE FROM <0> t WHERE (t.<2> = rec.<2>);
    EXCEPTION
      WHEN OTHERS THEN
          LogMergeError( ''<1>'', ''<2>'', rec.<2>);
    END;
  END LOOP;
END;';
BEGIN
  FOR tabcol IN (SELECT t.Tmp_Table_Name, t.Table_Name, c.Column_Name
                 FROM Tmp_Tables t,
                      User_Tab_Columns c
                 WHERE     (c.Table_Name = Upper( t.Tmp_Table_Name))
                       AND (c.Column_ID = 1)
            ) LOOP
    EXECUTE IMMEDIATE Replace( Replace( Replace( PLSQL_BLOCK,
                               '<0>', tabcol.Tmp_Table_Name),
                               '<1>', tabcol.Table_Name),
                               '<2>', tabcol.Column_Name);
  END LOOP;
END;
-- check the data after execution ...
SELECT * FROM TMP_KL002 ORDER BY K;
SELECT * FROM KL002 ORDER BY K;
SELECT * FROM TMP_TABLE1 ORDER BY NS;
SELECT * FROM TABLE1 ORDER BY NS;
-- ... and also the error-logging table
SELECT * FROM tbl_MergeErrors ORDER BY Stamp, TableName;
-- of couse you must issue an COMMIT (the ROLLBACK is only for testing
ROLLBACK WORK;
-- drop the test-tables
DROP TABLE TABLE1 PURGE;
DROP TABLE KL002 PURGE;
DROP TABLE TMP_TABLE1 PURGE;
DROP TABLE TMP_KL002 PURGE;
DROP TABLE TMP_TABLES PURGE;
-- you shouldn't drop the error-logging table, but I use it to free up my db
DROP TABLE tbl_MergeErrors PURGE;Greetings, Niels