Database migration from PostgreSQL to Oracle

Question

I am migrating my database server from PostgreSQL to Oracle 11g. I tried various tools like Squirrel SQL. But most of the migration tools support table and views to migrate. I cannot find a solution to migrate my procedures and functions. What is the way I can migrate the functions and procedures. Please find one of the functions below.

CREATE OR REPLACE FUNCTION hrms.fngetstatus(iactdate character varying, ideactdate character varying)
  RETURNS character varying AS
$BODY$
   returnval   VARCHAR (1);
BEGIN
   IF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                      TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
      AND TO_DATE (ideactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
        returnval := 'D';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') IS NULL
   THEN

       returnval := 'D';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
        returnval := 'A';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') IS NULL
   THEN
      returnval := 'A';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
      returnval := 'D';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') =
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') =
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
      returnval := 'D';
        ELSIF     TO_DATE (ideactdate, 'mm/dd/yyyy') >=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (iactdate, 'mm/dd/yyyy') is null                      
   THEN
      returnval := 'A';  
        ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')   
   THEN
      returnval := 'A';  
        ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')   
   THEN
      returnval := 'D';   
          ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')   
   THEN
      returnval := 'D';    
   END IF;
   RETURN returnval;
END$BODY$
  LANGUAGE edbspl VOLATILE SECURITY DEFINER
  COST 100;
ALTER FUNCTION hrms.fngetstatus(character varying, character varying)
  OWNER TO enterprisedb;

Different database engines do things differently. For example, oracle does not have two of the common date functions (dateadd, datediff) that you find in many other database engines. I think the only way to do this well is do it all manually so that you can test everything you do. — Dan Bracuk, Sep 26 '13 at 12:58
Can you give me a documentation where I can read the checklist to keep in mind while converting them manually? — Jeyasithar, Sep 26 '13 at 13:00
Why dont you think rewrite all of them. Oracle supports different builtin functions from Postgress — Ugur Artun, Sep 26 '13 at 13:10
@DanBracuk: you don't need the clumsy `dateadd` or `dateadd` in Oracle (or Postgres) because it supports ANSI SQL date arithmetics, e.g. `some_date + interval '1' week` or a bit simpler `current_date + 1` for "tomorrow" — , Sep 26 '13 at 13:10
The function I pasted is just an example. I tried to execute this directly to oracle sql console, getting lot of errors in the console. Ex. `ORA-06550: line 7, column 24: PLS-00103: Encountered the symbol "end-of-file" when expecting one of the following: * & = - + ; < / > at in is mod remainder not rem <> or != or ~= >= <= <> and or like like2 like4 likec between || multiset member submultiset ` — Jeyasithar, Sep 26 '13 at 13:15

score 3 · Accepted Answer · answered Sep 26 '13 at 13:14

The only thing you need to change is the code "around" the function. Oracle uses a different "header" than Postgres.

So the function in PL/SQL would look like this. I only changed the beginning CREATE OR REPLACE and the part after the final END.

CREATE OR REPLACE FUNCTION fngetstatus(iactdate varchar, ideactdate varchar)
  RETURN varchar 
AS
   returnval   VARCHAR (1);
BEGIN
   IF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                      TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
      AND TO_DATE (ideactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
        returnval := 'D';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') IS NULL
   THEN

       returnval := 'D';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
        returnval := 'A';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') IS NULL
   THEN
      returnval := 'A';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
      returnval := 'D';
   ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') =
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') =
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
   THEN
      returnval := 'D';
        ELSIF     TO_DATE (ideactdate, 'mm/dd/yyyy') >=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (iactdate, 'mm/dd/yyyy') is null                      
   THEN
      returnval := 'A';  
        ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')   
   THEN
      returnval := 'A';  
        ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')   
   THEN
      returnval := 'D';   
          ELSIF     TO_DATE (iactdate, 'mm/dd/yyyy') >
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')
         AND TO_DATE (ideactdate, 'mm/dd/yyyy') <=
                       TO_DATE (TO_CHAR (SYSDATE, 'mm/dd/yyyy'), 'mm/dd/yyyy')   
   THEN
      returnval := 'D';    
   END IF;
   RETURN returnval;
END;
/

Here is a SQLFiddle example: http://sqlfiddle.com/#!4/94990/2

I tried executing the query updated by you. Getting the following error `ORA-06550: line 7, column 24: PLS-00103: Encountered the symbol "end-of-file" when expecting one of the following: * & = - + ; < / > at in is mod remainder not rem <> or != or ~= >= <= <> and or like like2 like4 likec between || multiset member submultiset ` — Jeyasithar, Sep 26 '13 at 13:17
@Jeyasithar Then you are not telling us everything. See my SQLFiddle it *does* work. Does Squirrel support the `/` terminator for PL/SQL definitions? — , Sep 26 '13 at 13:18
I am using datasource explorer plugin in Eclipse to execute the query. — Jeyasithar, Sep 26 '13 at 13:20
@Jeyasithar: Sorry I don't use eclipse so I cannot comment on that. But apparently it does not support creating PL/SQL procedures. You should try SQL Developer, SQL*Plus or any other tool that can use an alternate delimiter (because that's what you need - most probably Eclipse sends everything to the first `;` because it doesn't recognize the `/`) — , Sep 26 '13 at 13:22

Database migration from PostgreSQL to Oracle

1 Answers1