PostgreSQL - Iterate over results of query

temprow is a record variable which is bound in turn to each record of the first SELECT.

So you should write:

FOR temprow IN        SELECT * FROM user_data.users ORDER BY user_seasonpts DESC LIMIT 10    LOOP        INSERT INTO user_data.leaderboards (season_num,player_id,season_pts) VALUES (old_seasonnum,temprow.userd_id,temprow.season_ptss);    END LOOP;

This loop could be further simplified as a single query:

INSERT INTO user_data.leaderboards (season_num,player_id,season_pts)SELECT old_seasonnum,player_idd,season_ptss FROM user_data.users ORDER BY user_seasonpts DESC LIMIT 10

A function that loop through the select and use loop item values to filter and calculate other values,

CREATE FUNCTION "UpdateTable"() RETURNS boolean    LANGUAGE plpgsqlAS$$DECLARE    TABLE_RECORD RECORD;    BasePrice NUMERIC;    PlatformFee NUMERIC;    MarketPrice NUMERIC;    FinalAmount NUMERIC;BEGIN    FOR TABLE_RECORD IN SELECT * FROM "SchemaName1"."TableName1" -- can select required fields only        LOOP            SELECT "BasePrice", "PlatformFee" INTO BasePrice, PlatformFee            FROM "SchemaName2"."TableName2" WHERE "UserID" = TABLE_RECORD."UserRID";            SELECT "MarketPrice" / 100 INTO MarketPrice FROM "SchemaName3"."TableName3" WHERE "DateTime" = TABLE_RECORD."DateTime";            FinalAmount = TABLE_RECORD."Qty" * (BasePrice + PlatformFee - MarketPrice);            UPDATE "SchemaName1"."TableName1" SET "MarketPrice" = MarketPrice, "Amount" = CFDAmount            WHERE "ID" = CFD_RECORD."ID"; -- can update other schema tables also        END LOOP;    RETURN TRUE;END$$;