Mysql Query Optimization for this particular query

Question

I am having a mysql query which is taking roughly 2.6s to execute. At first it was not using index. Now I added index to it. But still no improvements. Any suggestion on this:

select posummary0_.id                               as col_0_0_,
       popayment1_.status                           as col_1_0_,
       posummary0_.id                               as id1_11_,
       posummary0_.created_at                       as created_2_11_,
       posummary0_.created_by                       as created_3_11_,
       posummary0_.is_active                        as is_activ4_11_,
       posummary0_.updated_at                       as updated_5_11_,
       posummary0_.updated_by                       as updated_6_11_,
       posummary0_.uuid                             as uuid7_11_,
       posummary0_.additional_cost                  as addition8_11_,
       posummary0_.additional_cost_note             as addition9_11_,
       posummary0_.approved_at                      as approve10_11_,
       posummary0_.approved_by                      as approve11_11_,
       posummary0_.can_be_rejected                  as can_be_12_11_,
       posummary0_.close_reason                     as close_r13_11_,
       posummary0_.closed_at                        as closed_14_11_,
       posummary0_.closed_by                        as closed_15_11_,
       posummary0_.delivery_fee                     as deliver16_11_,
       posummary0_.eta_date                         as eta_dat17_11_,
       posummary0_.sku_farmer_id                    as sku_far35_11_,
       posummary0_.gr_price                         as gr_pric18_11_,
       posummary0_.invoice_date                     as invoice19_11_,
       posummary0_.is_vat                           as is_vat20_11_,
       posummary0_.payment_due_date                 as payment21_11_,
       posummary0_.payment_source                   as payment22_11_,
       posummary0_.po_discount                      as po_disc23_11_,
       posummary0_.po_number                        as po_numb24_11_,
       posummary0_.po_price                         as po_pric25_11_,
       posummary0_.po_status_id                     as po_stat36_11_,
       posummary0_.po_status_update_at              as po_stat26_11_,
       posummary0_.po_summary_payment_type_id       as po_summ37_11_,
       posummary0_.po_summary_type_id               as po_summ38_11_,
       posummary0_.po_vat_type_id                   as po_vat_39_11_,
       posummary0_.receipt_id_type                  as receipt27_11_,
       posummary0_.reject_reason                    as reject_28_11_,
       posummary0_.rejected_at                      as rejecte29_11_,
       posummary0_.rejected_by                      as rejecte30_11_,
       posummary0_.revised_at                       as revised31_11_,
       posummary0_.revised_by                       as revised32_11_,
       posummary0_.total_price                      as total_p33_11_,
       posummary0_.vat                              as vat34_11_,
       posummary0_.warehouse_id                     as warehou40_11_,
       posummary0_.warehouse_distribution_center_id as warehou41_11_,
       posummary0_.warehouse_kitchen_id             as warehou42_11_,
       posummary0_.warehouse_time_window_id         as warehou43_11_
from po_summaries posummary0_
         left outer join po_payments popayment1_ on (posummary0_.id = popayment1_.po_summary_id)
         cross join sku_farmers farmer2_
         cross join warehouses warehouse3_
         cross join po_status postatus4_
where posummary0_.sku_farmer_id = farmer2_.id
  and posummary0_.warehouse_id = warehouse3_.id
  and posummary0_.po_status_id = postatus4_.id
  and (1 is null or posummary0_.is_active = 1)
  and (null is null or posummary0_.created_at >= null)
  and (null is null or posummary0_.created_at <= null)
  and (null is null or posummary0_.eta_date >= null)
  and (null is null or posummary0_.eta_date <= null)
  and ('' is null or '' = '' or farmer2_.uuid = '')
  and ('' is null or '' = '' or warehouse3_.uuid = '')
  and ('%%' is null or '%%' = '' or postatus4_.code like '%')
  and ('%%' is null or '%%' = '' or posummary0_.po_number like '%')
  and (null is null or null = '' or posummary0_.created_by like null)
order by posummary0_.created_at desc
limit 160, 20;

the id field are already indexed. I additionally added index on this:

create index test_index_2 on po_status (code);

Before index explain output:

After index it became like this:

I am very new to mysql and need suggestion to improve performance.

One keynote: If I remove order by then the query execution time becomes so less.

Can anyone suggest me optimization for this query? Plan:

Answer 1

(I think that is the worst programmatically generated SQL that I have ever seen. What program created it? Still, it might actually work as it stands!)

This one composite index may be a partial salvation:

posummary0_:  INDEX(is_active, created_at)

and when may have to change

and  (1 is null
              or  posummary0_.is_active = 1
           )

to

and  posummary0_.is_active = 1

( OR is deadly for performance. This OR comes from a lazy query-generator.)

If you feed it different options, you may need another INDEX.

After cleaning up the query, we can talk about turning it inside-out. This will allow the ORDER BY , OFFSET , and LIMIT to occur before all the JOINs . Currently the query is doing 57414 4 joins. With the reformulation, it will need only 10 4.

Inside out

First, see if this provides the desired 20 ids and runs 'fast':

select  posummary0_.id
    posummary0_.is_active = 1
    order by  posummary0_.created_at desc
    limit  160, 20;

Then build a query something like

SELECT ...  -- mostly as above
    FROM ( the 4 lines above ) AS x
    JOIN ...   -- the rest of the SQL, but without the LIMIT