w-BIG TABLE-view+where-small table

w-BIG TABLE

DROP PROCEDURE IF EXISTS truncate_insert_sales_rank_toparow_month;
DELIMITER /w/
CREATE PROCEDURE truncate_insert_sales_rank_toparow_month ()
BEGIN
TRUNCATE sales_rank_toparow_month ;
INSERT INTO sales_rank_toparow_month (
    fk_countrycode,
    fk_categoryid,
    history_year,
    history_month
) SELECT
    country,
    categoryid,
    grab_year,
    grab_month
FROM
    grab_sales_rank_month
GROUP BY
    country,
    categoryid,
    grab_year,
    grab_month ;
END/w/
DELIMITER;
CALL truncate_insert_sales_rank_toparow_month;

DROP PROCEDURE IF EXISTS insert_update_sales_rank_toparow_month;
DELIMITER /w/
CREATE PROCEDURE insert_update_sales_rank_toparow_month ()
BEGIN
SET @wtab = ' sales_rank_toparow_month  ';
SET @wtab_src = 'grab_sales_rank_month';
SET @w = 10;
SET @wyear_max=(SELECT MAX(grab_year) FROM grab_sales_rank_month)+1;
SET @wyear = (SELECT MIN(grab_year) FROM grab_sales_rank_month);

WHILE @w < 101 DO
    WHILE @wyear < @wyear_max DO
        SET @wmonth=(SELECT MIN(grab_month) FROM grab_sales_rank_month WHERE grab_year=@wyear);
        SET @wmonth_max=(SELECT MAX(grab_month) FROM grab_sales_rank_month WHERE grab_year=@wyear)+1;
        WHILE @wmonth < @wmonth_max DO

                DROP VIEW IF EXISTS    wview;
                SET @wview_where = CONCAT(' WHERE grab_year=',@wyear,' AND grab_month=',@wmonth,' AND topx=',@w);
                SET @wview =  CONCAT('CREATE VIEW wview AS SELECT * FROM ',@wtab_src,@wview_where,';');
                PREPARE  stmt0 FROM @wview ;
                EXECUTE  stmt0  ;
                DROP PREPARE stmt0;

                DROP VIEW IF EXISTS    wview1;
                SET @wview1_where =  CONCAT(' WHERE history_year=',@wyear,' AND history_month=',@wmonth,';');
                SET @wview1 =  CONCAT('CREATE VIEW wview1 AS SELECT * FROM ',@wtab,@wview1_where,';');
                PREPARE  stmt2 FROM @wview1 ;
                EXECUTE  stmt2  ;
                DROP PREPARE stmt2;

                SET @wfield = CONCAT('coin',@w);
                SET @wnewvalue = CONCAT('(SELECT sum_coin FROM wview da  WHERE  wview1.fk_countrycode = da.country  AND wview1.fk_categoryid = da.categoryid AND wview1.history_year = da.grab_year AND wview1.history_month = da.grab_month  AND da.topx=',@w,'  )');
                SET @wfieldb = CONCAT('amount',@w);
                SET @wnewvalueb = CONCAT('(SELECT sum_amount FROM wview da  WHERE  wview1.fk_countrycode = da.country  AND wview1.fk_categoryid = da.categoryid AND wview1.history_year = da.grab_year AND wview1.history_month = da.grab_month  AND da.topx=',@w,'  )');
                                
                SET @wpre = CONCAT('UPDATE ',' wview1 ',' SET ',@wfield,'=',@wnewvalue,',',@wfieldb,'=',@wnewvalueb);
                PREPARE  stmt1 FROM @wpre ;
                EXECUTE  stmt1  ;
                DROP PREPARE stmt1;

        SET @wmonth=@wmonth+1;
        END WHILE ;
    SET @wyear=@wyear+1;
    END WHILE ;
SET @wyear = (SELECT MIN(grab_year) FROM grab_sales_rank_month);
SET @w=@w+10;
END WHILE ;
END/w/
DELIMITER ;
CALL insert_update_sales_rank_toparow_month;

CREATE INDEX w1 ON grab_sales_rank_month (country);
CREATE INDEX w11 ON grab_sales_rank_month (categoryid);
CREATE INDEX w12 ON grab_sales_rank_month (grab_year);
CREATE INDEX w13 ON grab_sales_rank_month (topx);

USING BTREE  --->BETTER--->USING HASH