How can i combine multiple functions into one in postgresql? - postgresql

Question

I wrote a series of functions updating a progress column in my project, I wonder if this can be combined into a single function. I tried it, using SELECT * FROM schema.table; IF, ELSE IF ... THEN UPDATE column SET progress = xx however all i got was syntax errors on various lines, with which i couldn't figure out what i did wrong.
I would appreciate ideas as to what i did wrong or how i could achieve a single function in a different way, THANKS GUYS :)
This is the code, that worked, but i want to shorten:
CREATE OR REPLACE FUNCTION progress_update25() RETURNS void AS $$
BEGIN
UPDATE schema.table SET progress = 25 WHERE on_side_inspection = 'done';
END;
$$ LANGUAGE plpgsql;
CREATE OR REPLACE FUNCTION progress_update50() RETURNS void AS $$
BEGIN
UPDATE schema.table SET progress = 50 WHERE statement = 'requested' OR statement = 'received';
END;
$$ LANGUAGE plpgsql;
CREATE OR REPLACE FUNCTION progress_update75() RETURNS void AS $$
BEGIN
UPDATE schema.table SET progress = 75 WHERE
permit_01 = 'requested' OR permit_01 = 'permitted' OR permit_01 = 'n/a'
AND permit_02 = 'requested' OR permit_02 = 'permitted' OR permit_02 = 'n/a'
AND permit_03 = 'requested' OR permit_03 = 'permitted' OR permit_03 = 'n/a'
AND permit_04 = 'requested' OR permit_04 = 'permitted' OR permit_04 = 'n/a';
END;
$$ LANGUAGE plpgsql;
CREATE OR REPLACE FUNCTION progress_update90() RETURNS void AS $$
BEGIN
UPDATE schema.table SET progress = 90 WHERE permits_complete = 'complete';
END;
$$ LANGUAGE plpgsql;
CREATE OR REPLACE FUNCTION progress_update100() RETURNS void AS $$
BEGIN
UPDATE schema.table SET progress = 100 WHERE documentation = 'submitted';
END;
$$ LANGUAGE plpgsql;
This is the code, thats not working:
CREATE OR REPLACE FUNCTION progress_update() RETURNS void AS $$
BEGIN
SELECT * FROM schema.table;
IF on_side_inspection = 'done'
THEN UPDATE table SET progress = 25;
ELSE IF statement = 'requested' OR statement = 'received'
THEN UPDATE table SET progress = 50;
ELSE IF permit_01 = 'requested' OR permit_01 = 'permitted' OR permit_01 = 'n/a'
AND permit_02 = 'requested' OR permit_02 = 'permitted' OR permit_02 = 'n/a'
AND permit_03 = 'requested' OR permit_03 = 'permitted' OR permit_03 = 'n/a'
AND permit_04 = 'requested' OR permit_04 = 'permitted' OR permit_04 = 'n/a'
THEN UPDATE table SET progress = 75;
ELSE IF permits_complete = 'complete'
THEN UPDATE table SET progress = 90;
ELSE IF documentation = 'submitted'
THEN UPDATE table SET progress = 100;
END IF;
END;
$$ LANGUAGE plpgsql;

Answer 1

There are lot of issues - undeclared variables, missing INTO clause or badly used IF statement:
You do:
IF ... THEN
ELSE IF THEN
END IF;
It can work in some other languages, but not in Postgres. It should to be
IF ... THEN
ELSEIF ... THEN
END IF;