Postgresql 9.2 - Pourquoi la différence de vitesse - SQL Subselect et JOIN?

Question

J'essaie d'interroger la base de données d'un autre logiciel et je n'ai donc aucun contrôle sur la création d'index, de fonctions, etc. J'ai un accès en lecture seule, donc je ne pense pas pouvoir créer une table temporaire. Je ne peux pas comprendre pourquoi la différence.

Voici ma requête de base:

WITH vCriteria AS (
    SELECT vSub.visit_id, vd.vdiag_diag from visit vSUB 
    JOIN insurance_company_table1 inscomp1 ON inscomp1.inscomp1_comp = vSub.visit_ins 
     and inscomp1.inscomp1_arid = vSub.visit_arid 
    JOIN da152 da ON da.da152_arid = vSub.visit_arid 
    LEFT JOIN insurance1 i ON i.is1_num = vSub.visit_id AND i.is1_ins_full = vSub.visit_ins 
    LEFT JOIN visit_diagnosis vd ON vd.vdiag_visit_key = vSub.visit_id 

    WHERE vSub.visit_mr_fdt 
    BETWEEN (now() - 50 * INTERVAL '1 day') AND (now() + 10 * INTERVAL '1 day') 
    AND NULLIF (vSub.visit_disch_date, '0001-01-01' ::date) IS NOT NULL 
    AND Now() >=(vSub.visit_disch_date + inscomp1.inscomp1_lagdays * INTERVAL '1 day') 
    AND vSub.visit_servicecd_key ~ '^[0-9]+$|[FHJbKkN\\+]' = false 
    AND LEFT (vSub.visit_id, 1) NOT IN ('F', 'P', 'J') 
    AND NULLIF (i.is1_bill_dt, '0001-01-01' ::date) IS NULL 
    AND vSub.visit_disch_date <= da.da152_chgdt 
) 

Select vCriteria.* from vCriteria 

Il exécute en 609 ms

ajouter 1 rejoindre et il faut beaucoup plus: LEFT JOIN vd visit_diagnosis SUR vd.vdiag_visit_key = VSUB. visit_id

WITH vCriteria AS (
    SELECT vSub.visit_id, vd.vdiag_diag from visit vSUB 
    JOIN insurance_company_table1 inscomp1 ON inscomp1.inscomp1_comp = vSub.visit_ins 
     and inscomp1.inscomp1_arid = vSub.visit_arid 
    JOIN da152 da ON da.da152_arid = vSub.visit_arid 
    LEFT JOIN insurance1 i ON i.is1_num = vSub.visit_id AND i.is1_ins_full = vSub.visit_ins 
    LEFT JOIN visit_diagnosis vd ON vd.vdiag_visit_key = vSub.visit_id 

    WHERE vSub.visit_mr_fdt 
    BETWEEN (now() - 50 * INTERVAL '1 day') AND (now() + 10 * INTERVAL '1 day') 
    AND NULLIF (vSub.visit_disch_date, '0001-01-01' ::date) IS NOT NULL 
    AND Now() >=(vSub.visit_disch_date + inscomp1.inscomp1_lagdays * INTERVAL '1 day') 
    AND vSub.visit_servicecd_key ~ '^[0-9]+$|[FHJbKkN\\+]' = false 
    AND LEFT (vSub.visit_id, 1) NOT IN ('F', 'P', 'J') 
    AND NULLIF (i.is1_bill_dt, '0001-01-01' ::date) IS NULL 
    AND vSub.visit_disch_date <= da.da152_chgdt 
) 

Select vCriteria.* from vCriteria 

Il faut plus de 13 secondes pour exécuter

Donc, avec la requête ci-dessus très simplifiée voici des exemples que j'ai essayé. Si je fais quelque chose comme ceci:

SELECT t.id_field from table t 
JOIN . . . 
JOIN . . .  
WHERE <10 rows of filtering criteria> 

il exécute en 766 ms et ramène 411 dossiers

Quand je lance cette requête seule:

select t.id_field, t2.field1 from table t 
LEFT JOIN table2 t2 ON t2.t_id_field = t.id_field 
WHERE t.id_field in (<I list out the varchar(8) values here from first query>) 

Il exécute en 3,031 sec

Mais si j'essaie de mettre les requêtes ensemble, comme ceci

select t.id_field, t2.field1 from table t 
LEFT JOIN table2 t2 ON t2.t_id_field = t.id_field 
WHERE t.id_field in ( 
    SELECT t.id_field from table t 
    JOIN . . . 
    JOIN . . .  
    WHERE <10 rows of filtering criteria> 
) 

Il faut 19,406 sec

J'ai essayé WITH comme ceci:

WITH vt AS (
    SELECT t.id_field from table t 
    JOIN . . . 
    JOIN . . .  
    WHERE <10 rows of filtering criteria> 
) 
select vt.id_field, t2.field1 from vt 
LEFT JOIN table2 t2 ON t2.t_id_field = vt.id_field 

Il exécute en 12 secondes

J'ai essayé:

select t.id_field, t2.field1 from ( 
     SELECT tsub.id_field from table tsub 
     JOIN . . . 
     JOIN . . .  
     WHERE <10 rows of filtering criteria> 
    ) t 
LEFT JOIN table2 t2 ON t2.t_id_field = t.id_field 

Exécute en 12.750 sec

Un autre essai est ceci:

SELECT t.id_field, t2.field1 from table t 
JOIN . . . 
JOIN . . . 
LEFT JOIN table2 t2 ON t2.t_id_field = t.id_field 
WHERE <10 rows of filtering criteria> 

Fait à 12,813 sec

Toute réflexion sur la façon de l'obtenir au moins être 3 secondes comme celle-ci où je viens de mettre les valeurs manuellement?

Tel est le plan d'exécution

QUERY PLAN 
Nested Loop Left Join (cost=109243.37..119017.89 rows=1 width=83) 
    CTE vc 
    -> Nested Loop (cost=14871.86..109243.37 rows=1 width=7) 
      -> Nested Loop (cost=14871.86..109242.01 rows=4 width=24) 
       Join Filter: ((vsub.visit_disch_date <= da.da152_chgdt) AND (vsub.visit_arid = da.da152_arid)) 
       -> Index Scan using da152_pkey on da152 da (cost=0.00..10.40 rows=4 width=9) 
       -> Materialize (cost=14871.86..109230.80 rows=12 width=19) 
         -> Hash Right Join (cost=14871.86..109230.74 rows=12 width=19) 
          Hash Cond: (((i.is1_num)::text = (vsub.visit_id)::text) AND ((i.is1_ins_full)::text = (vsub.visit_ins)::text)) 
          Filter: (NULLIF(i.is1_bill_dt, '0001-01-01'::date) IS NULL) 
          -> Seq Scan on insurance1 i (cost=0.00..90993.64 rows=336264 width=14) 
          -> Hash (cost=14837.16..14837.16 rows=2313 width=19) 
            -> Seq Scan on visit vsub (cost=0.00..14837.16 rows=2313 width=19) 
             Filter: ((NULLIF(visit_disch_date, '0001-01-01'::date) IS NOT NULL) AND ((visit_servicecd_key)::text !~ '^[0-9]+$|[FHJbKkN\\+]'::text) AND ("left"((visit_id)::text, 1) <> ALL ('{F,P,J}'::text[])) AND (visit_mr_fdt >= (now() - '50 days'::interval)) AND (visit_mr_fdt <= (now() + '10 days'::interval))) 
      -> Index Scan using inscomp1_pkey on insurance_company_table1 inscomp1 (cost=0.00..0.33 rows=1 width=11) 
       Index Cond: ((inscomp1_arid = vsub.visit_arid) AND ((inscomp1_comp)::text = (vsub.visit_ins)::text)) 
       Filter: (now() >= (vsub.visit_disch_date + ((inscomp1_lagdays)::double precision * '1 day'::interval))) 
    -> CTE Scan on vc (cost=0.00..0.02 rows=1 width=12) 
    -> Index Scan using vdiag_pkey on visit_diagnosis vd (cost=0.00..9774.48 rows=1 width=71) 
     Index Cond: ((vdiag_visit_key)::text = (vc.visit_id)::text) 
     Filter: ((vdiag_type)::text = 'A'::text) 

Et Explain (Analyze, verbeux) (POUR "AVEC" QUERY EXEMPLE CI-DESSUS)

QUERY PLAN 
Nested Loop Left Join (cost=109243.36..119017.87 rows=1 width=83) (actual time=418.062..13796.260 rows=414 loops=1) 
    Output: vc.visit_id, vd.vdiag_visit_key, vd.vdiag_arxseq, vd.vdiag_element, vd.vdiag_type, vd.vdiag_date, vd.vdiag_diag, vd.vdiag_arid 
    CTE vc 
    -> Nested Loop (cost=14871.84..109243.36 rows=1 width=7) (actual time=404.477..1006.518 rows=414 loops=1) 
      Output: vsub.visit_id 
      -> Nested Loop (cost=14871.84..109242.00 rows=4 width=24) (actual time=404.432..990.137 rows=418 loops=1) 
       Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date, da.da152_arid 
       Join Filter: ((vsub.visit_disch_date <= da.da152_chgdt) AND (vsub.visit_arid = da.da152_arid)) 
       Rows Removed by Join Filter: 1374 
       -> Index Scan using da152_pkey on public.da152 da (cost=0.00..10.40 rows=4 width=9) (actual time=0.004..0.017 rows=4 loops=1) 
         Output: da.da152_rel_file_key_num, da.da152_contrl, da.da152_rcdt, da.da152_chgdt, da.da152_ar_rev, da.da152_ar_rc, da.da152_ar_rcar, da.da152_unpost, da.da152_lrun, da.da152_ar_month, da.da152_insdt, da.da152_otc_rcdt, da.da152_sum_rev, da.da152_sum_rc, da.da152_sum_rcar, da.da152_begbal, da.da152_netar, da.da152_arend, da.da152_eomtrial, da.da152_rc_da, da.da152_rc_amt_otc, da.da152_rc_amt_cp, da.da152_chg_thru, da.da152_ar_ldom, da.da152_csnum, da.da152_sec_e_bill, da.da152_uform, da.da152_jform, da.da152_rate, da.da152_contract_bill, da.da152_up_front, da.da152_bad_debt, da.da152_pat_refund, da.da152_2cnd_ins, da.da152_pat_type1, da.da152_pat_type2, da.da152_pat_srvcd1_old, da.da152_pat_srvcd2_old, da.da152_wo_colcd1, da.da152_wo_alpha1s, da.da152_wo_alpha1e, da.da152_wo_colcd2, da.da152_wo_alpha2s, da.da152_wo_alpha2e, da.da152_wo_colcd3, da.da152_wo_alpha3s, da.da152_wo_alpha3e, da.da152_ins_prim, da.da152_tic_xfc1, da.da152_tic_xfc2, da.da152_ins_fc, da.da152_wo_sitnum, da.da152_wo_sit_cd, da.da152_ins2dt, da.da152_multicoqual, da.da152_multicoid, da.da152_multicodir, da.da152_multicoglnum, da.da152_pat_srvcd1, da.da152_pat_srvcd2, da.da152_adchg, da.da152_adchg_var, da.da152_month_closedt, da.da152_pat_colcd, da.da152_nonaracct, da.da152_isfup_days, da.da152_arid 
       -> Materialize (cost=14871.84..109230.79 rows=12 width=19) (actual time=101.103..246.563 rows=448 loops=4) 
         Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
         -> Hash Right Join (cost=14871.84..109230.73 rows=12 width=19) (actual time=404.408..983.328 rows=448 loops=1) 
          Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
          Hash Cond: (((i.is1_num)::text = (vsub.visit_id)::text) AND ((i.is1_ins_full)::text = (vsub.visit_ins)::text)) 
          Filter: (NULLIF(i.is1_bill_dt, '0001-01-01'::date) IS NULL) 
          Rows Removed by Filter: 2018 
          -> Seq Scan on public.insurance1 i (cost=0.00..90993.64 rows=336264 width=14) (actual time=0.002..284.366 rows=341073 loops=1) 
            Output: i.is1_num, i.is1_ins_full, i.is1_set, i.is1_prim, i.is1_stay, i.is1_direct, i.is1_admit, i.is1_disc, i.is1_from, i.is1_to, i.is1_app_sent, i.is1_app_rec, i.is1_gen_dt, i.is1_ck_dt, i.is1_contract_old, i.is1_bill_dt, i.is1_pd_dt1, i.is1_pd_amt1, i.is1_pd_dt2, i.is1_pd_amt2, i.is1_pd_dt3, i.is1_pd_amt3, i.is1_pd_status, i.is1_med_ness, i.is1_bl_furn, i.is1_bl_rep, i.is1_bl_n_rep, i.is1_bl_rate, i.is1_bl_chg, i.is1_bl_non, i.is1_coamt, i.is1_expay, i.is1_semi_rate, i.is1_diem, i.is1_cd, i.is1_typrm, i.is1_qty, i.is1_chg, i.is1_non, i.is1_opcd, i.is1_opdate, i.is1_opdesc, i.is1_opchg, i.is1_opphy, i.is1_totchg, i.is1_totnon, i.is1_maxlines, i.is1_totlines, i.is1_apc_sw, i.is1_eapc_reim, i.is1_eapc_copay, i.is1_eapc_contr, i.is1_eapc_ded, i.is1_eapc_outlr, i.is1_aapc_reim, i.is1_aapc_copay, i.is1_aapc_contr, i.is1_aapc_ded, i.is1_aapc_outlr, i.is1_mr_okayed, i.is1_mr_ok_init, i.is1_a_ded, i.is1_dayfull, i.is1_dayco, i.is1_daylife, i.is1_bl_ded, i.is1_bl_d_amt, i.is1_contr2, i.is1_copay, i.is1_colim, i.is1_covrmrate, i.is1_lifeused, i.is1_covdays, i.is1_nondays, i.is1_co_used, i.is1_typary, i.is1_effdt, i.is1_covrate, i.is1_endcare, i.is1_drg, i.is1_p_name, i.is1_birth, i.is1_print, i.is1_mndays, i.is1_reim_amt, i.is1_elecbill, i.is1_elecdate, i.is1_ppscode, i.is1_psrocode, i.is1_typebill, i.is1_new_op_medicare, i.is1_netreim, i.is1_serv, i.is1_printcross, i.is1_crossdate, i.is1_filetype, i.is1_releaseinfo, i.is1_pdtype1, i.is1_pdtype2, i.is1_pdtype3, i.is1_coins, i.is1_otprim, i.is1_otins, i.is1_otset, i.is1_coveragesetby, i.is1_covcalctype, i.is1_covverified, i.is1_netcalc, i.is1_orig_expay, i.is1_orig_bl_d_amt, i.is1_orig_coamt, i.is1_orig_a_ded, i.is1_orig_drg, i.is1_orig_covdays, i.is1_excrep, i.is1_exccov, i.is1_genviaautocl, i.is1_autobill, i.is1_formver, i.is1_contract, i.is1_origin, i.is1_covgoverride, i.is1_covglogname, i.is1_covgcsnum, i.is1_excchgs, i.is1_arid, i.is1_drg_icd10 
          -> Hash (cost=14837.16..14837.16 rows=2312 width=19) (actual time=394.738..394.738 rows=2416 loops=1) 
            Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
            Buckets: 1024 Batches: 1 Memory Usage: 123kB 
            -> Seq Scan on public.visit vsub (cost=0.00..14837.16 rows=2312 width=19) (actual time=0.097..391.839 rows=2416 loops=1) 
             Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
             Filter: ((NULLIF(vsub.visit_disch_date, '0001-01-01'::date) IS NOT NULL) AND ((vsub.visit_servicecd_key)::text !~ '^[0-9]+$|[FHJbKkN\\+]'::text) AND ("left"((vsub.visit_id)::text, 1) <> ALL ('{F,P,J}'::text[])) AND (vsub.visit_mr_fdt >= (now() - '50 days'::interval)) AND (vsub.visit_mr_fdt <= (now() + '10 days'::interval))) 
             Rows Removed by Filter: 201579 
      -> Index Scan using inscomp1_pkey on public.insurance_company_table1 inscomp1 (cost=0.00..0.33 rows=1 width=11) (actual time=0.029..0.031 rows=1 loops=418) 
       Output: inscomp1.inscomp1_comp, inscomp1.inscomp1_name, inscomp1.inscomp1_addr1, inscomp1.inscomp1_addr2, inscomp1.inscomp1_city, inscomp1.inscomp1_state, inscomp1.inscomp1_zip, inscomp1.inscomp1_form, inscomp1.inscomp1_jour, inscomp1.inscomp1_prov, inscomp1.inscomp1_typebill, inscomp1.inscomp1_perdiem, inscomp1.inscomp1_diemdt, inscomp1.inscomp1_priordiem, inscomp1.inscomp1_pcused, inscomp1.inscomp1_phybillsw, inscomp1.inscomp1_approval, inscomp1.inscomp1_psro, inscomp1.inscomp1_ask_reim, inscomp1.inscomp1_reject_days, inscomp1.inscomp1_contrgl, inscomp1.inscomp1_othargl, inscomp1.inscomp1_auto_ip, inscomp1.inscomp1_auto_op, inscomp1.inscomp1_prirate, inscomp1.inscomp1_secrate, inscomp1.inscomp1_lagdays, inscomp1.inscomp1_mul1500, inscomp1.inscomp1_waitfin, inscomp1.inscomp1_opsum, inscomp1.inscomp1_write_off, inscomp1.inscomp1_transmit, inscomp1.inscomp1_detail_bl, inscomp1.inscomp1_provname, inscomp1.inscomp1_provaddr1, inscomp1.inscomp1_provaddr2, inscomp1.inscomp1_provcity, inscomp1.inscomp1_provst, inscomp1.inscomp1_provzip, inscomp1.inscomp1_cont_perc, inscomp1.inscomp1_drg_str, inscomp1.inscomp1_drg_acps, inscomp1.inscomp1_drg_dt, inscomp1.inscomp1_ub_loc2, inscomp1.inscomp1_sub_id, inscomp1.inscomp1_bcno, inscomp1.inscomp1_taxno, inscomp1.inscomp1_mcareno, inscomp1.inscomp1_mcaidno, inscomp1.inscomp1_signature, inscomp1.inscomp1_prov2, inscomp1.inscomp1_allpay, inscomp1.inscomp1_discrate, inscomp1.inscomp1_discdt, inscomp1.inscomp1_discrate2, inscomp1.inscomp1_sumitem, inscomp1.inscomp1_bank_plan, inscomp1.inscomp1_phy_1500, inscomp1.inscomp1_labmc, inscomp1.inscomp1_orer_comb, inscomp1.inscomp1_phybillex, inscomp1.inscomp1_net_reim, inscomp1.inscomp1_ask_drg, inscomp1.inscomp1_provphone, inscomp1.inscomp1_drggroup, inscomp1.inscomp1_phyins, inscomp1.inscomp1_phyub82, inscomp1.inscomp1_mnxsnf, inscomp1.inscomp1_srcpmtcde, inscomp1.inscomp1_provname2, inscomp1.inscomp1_coll_id, inscomp1.inscomp1_diagptr, inscomp1.inscomp1_tax, inscomp1.inscomp1_type_desc, inscomp1.inscomp1_revcode, inscomp1.inscomp1_arid 
       Index Cond: ((inscomp1.inscomp1_arid = vsub.visit_arid) AND ((inscomp1.inscomp1_comp)::text = (vsub.visit_ins)::text)) 
       Filter: (now() >= (vsub.visit_disch_date + ((inscomp1.inscomp1_lagdays)::double precision * '1 day'::interval))) 
    -> CTE Scan on vc (cost=0.00..0.02 rows=1 width=12) (actual time=404.481..1008.180 rows=414 loops=1) 
     Output: vc.visit_id 
    -> Index Scan using vdiag_pkey on public.visit_diagnosis vd (cost=0.00..9774.48 rows=1 width=71) (actual time=14.246..30.882 rows=1 loops=414) 
     Output: vd.vdiag_visit_key, vd.vdiag_arxseq, vd.vdiag_element, vd.vdiag_type, vd.vdiag_date, vd.vdiag_diag, vd.vdiag_arid 
     Index Cond: ((vd.vdiag_visit_key)::text = (vc.visit_id)::text) 
     Filter: ((vd.vdiag_type)::text = 'A'::text) 
     Rows Removed by Filter: 1 
Total runtime: 13796.881 ms 

EXPLIQUER (ANALYSER, verbeux) POUR OBTENIR JUSTE ID'S INTERVENUES MILLISECONDES

QUERY PLAN 
Nested Loop (cost=14871.84..109244.42 rows=1 width=7) (actual time=403.659..985.167 rows=432 loops=1) 
    Output: vsub.visit_id 
    -> Nested Loop (cost=14871.84..109243.06 rows=4 width=24) (actual time=403.618..980.483 rows=441 loops=1) 
     Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date, da.da152_arid 
     Join Filter: ((vsub.visit_disch_date <= da.da152_chgdt) AND (vsub.visit_arid = da.da152_arid)) 
     Rows Removed by Join Filter: 1351 
     -> Index Scan using da152_pkey on public.da152 da (cost=0.00..10.40 rows=4 width=9) (actual time=0.004..0.014 rows=4 loops=1) 
       Output: da.da152_rel_file_key_num, da.da152_contrl, da.da152_rcdt, da.da152_chgdt, da.da152_ar_rev, da.da152_ar_rc, da.da152_ar_rcar, da.da152_unpost, da.da152_lrun, da.da152_ar_month, da.da152_insdt, da.da152_otc_rcdt, da.da152_sum_rev, da.da152_sum_rc, da.da152_sum_rcar, da.da152_begbal, da.da152_netar, da.da152_arend, da.da152_eomtrial, da.da152_rc_da, da.da152_rc_amt_otc, da.da152_rc_amt_cp, da.da152_chg_thru, da.da152_ar_ldom, da.da152_csnum, da.da152_sec_e_bill, da.da152_uform, da.da152_jform, da.da152_rate, da.da152_contract_bill, da.da152_up_front, da.da152_bad_debt, da.da152_pat_refund, da.da152_2cnd_ins, da.da152_pat_type1, da.da152_pat_type2, da.da152_pat_srvcd1_old, da.da152_pat_srvcd2_old, da.da152_wo_colcd1, da.da152_wo_alpha1s, da.da152_wo_alpha1e, da.da152_wo_colcd2, da.da152_wo_alpha2s, da.da152_wo_alpha2e, da.da152_wo_colcd3, da.da152_wo_alpha3s, da.da152_wo_alpha3e, da.da152_ins_prim, da.da152_tic_xfc1, da.da152_tic_xfc2, da.da152_ins_fc, da.da152_wo_sitnum, da.da152_wo_sit_cd, da.da152_ins2dt, da.da152_multicoqual, da.da152_multicoid, da.da152_multicodir, da.da152_multicoglnum, da.da152_pat_srvcd1, da.da152_pat_srvcd2, da.da152_adchg, da.da152_adchg_var, da.da152_month_closedt, da.da152_pat_colcd, da.da152_nonaracct, da.da152_isfup_days, da.da152_arid 
     -> Materialize (cost=14871.84..109231.85 rows=12 width=19) (actual time=100.901..244.629 rows=448 loops=4) 
       Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
       -> Hash Right Join (cost=14871.84..109231.79 rows=12 width=19) (actual time=403.596..976.869 rows=448 loops=1) 
        Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
        Hash Cond: (((i.is1_num)::text = (vsub.visit_id)::text) AND ((i.is1_ins_full)::text = (vsub.visit_ins)::text)) 
        Filter: (NULLIF(i.is1_bill_dt, '0001-01-01'::date) IS NULL) 
        Rows Removed by Filter: 2018 
        -> Seq Scan on public.insurance1 i (cost=0.00..90994.67 rows=336267 width=14) (actual time=0.002..283.076 rows=341075 loops=1) 
          Output: i.is1_num, i.is1_ins_full, i.is1_set, i.is1_prim, i.is1_stay, i.is1_direct, i.is1_admit, i.is1_disc, i.is1_from, i.is1_to, i.is1_app_sent, i.is1_app_rec, i.is1_gen_dt, i.is1_ck_dt, i.is1_contract_old, i.is1_bill_dt, i.is1_pd_dt1, i.is1_pd_amt1, i.is1_pd_dt2, i.is1_pd_amt2, i.is1_pd_dt3, i.is1_pd_amt3, i.is1_pd_status, i.is1_med_ness, i.is1_bl_furn, i.is1_bl_rep, i.is1_bl_n_rep, i.is1_bl_rate, i.is1_bl_chg, i.is1_bl_non, i.is1_coamt, i.is1_expay, i.is1_semi_rate, i.is1_diem, i.is1_cd, i.is1_typrm, i.is1_qty, i.is1_chg, i.is1_non, i.is1_opcd, i.is1_opdate, i.is1_opdesc, i.is1_opchg, i.is1_opphy, i.is1_totchg, i.is1_totnon, i.is1_maxlines, i.is1_totlines, i.is1_apc_sw, i.is1_eapc_reim, i.is1_eapc_copay, i.is1_eapc_contr, i.is1_eapc_ded, i.is1_eapc_outlr, i.is1_aapc_reim, i.is1_aapc_copay, i.is1_aapc_contr, i.is1_aapc_ded, i.is1_aapc_outlr, i.is1_mr_okayed, i.is1_mr_ok_init, i.is1_a_ded, i.is1_dayfull, i.is1_dayco, i.is1_daylife, i.is1_bl_ded, i.is1_bl_d_amt, i.is1_contr2, i.is1_copay, i.is1_colim, i.is1_covrmrate, i.is1_lifeused, i.is1_covdays, i.is1_nondays, i.is1_co_used, i.is1_typary, i.is1_effdt, i.is1_covrate, i.is1_endcare, i.is1_drg, i.is1_p_name, i.is1_birth, i.is1_print, i.is1_mndays, i.is1_reim_amt, i.is1_elecbill, i.is1_elecdate, i.is1_ppscode, i.is1_psrocode, i.is1_typebill, i.is1_new_op_medicare, i.is1_netreim, i.is1_serv, i.is1_printcross, i.is1_crossdate, i.is1_filetype, i.is1_releaseinfo, i.is1_pdtype1, i.is1_pdtype2, i.is1_pdtype3, i.is1_coins, i.is1_otprim, i.is1_otins, i.is1_otset, i.is1_coveragesetby, i.is1_covcalctype, i.is1_covverified, i.is1_netcalc, i.is1_orig_expay, i.is1_orig_bl_d_amt, i.is1_orig_coamt, i.is1_orig_a_ded, i.is1_orig_drg, i.is1_orig_covdays, i.is1_excrep, i.is1_exccov, i.is1_genviaautocl, i.is1_autobill, i.is1_formver, i.is1_contract, i.is1_origin, i.is1_covgoverride, i.is1_covglogname, i.is1_covgcsnum, i.is1_excchgs, i.is1_arid, i.is1_drg_icd10 
        -> Hash (cost=14837.16..14837.16 rows=2312 width=19) (actual time=393.928..393.928 rows=2416 loops=1) 
          Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
          Buckets: 1024 Batches: 1 Memory Usage: 123kB 
          -> Seq Scan on public.visit vsub (cost=0.00..14837.16 rows=2312 width=19) (actual time=0.088..391.163 rows=2416 loops=1) 
           Output: vsub.visit_id, vsub.visit_ins, vsub.visit_arid, vsub.visit_disch_date 
           Filter: ((NULLIF(vsub.visit_disch_date, '0001-01-01'::date) IS NOT NULL) AND ((vsub.visit_servicecd_key)::text !~ '^[0-9]+$|[FHJbKkN\\+]'::text) AND ("left"((vsub.visit_id)::text, 1) <> ALL ('{F,P,J}'::text[])) AND (vsub.visit_mr_fdt >= (now() - '50 days'::interval)) AND (vsub.visit_mr_fdt <= (now() + '10 days'::interval))) 
           Rows Removed by Filter: 201581 
    -> Index Scan using inscomp1_pkey on public.insurance_company_table1 inscomp1 (cost=0.00..0.33 rows=1 width=11) (actual time=0.007..0.008 rows=1 loops=441) 
     Output: inscomp1.inscomp1_comp, inscomp1.inscomp1_name, inscomp1.inscomp1_addr1, inscomp1.inscomp1_addr2, inscomp1.inscomp1_city, inscomp1.inscomp1_state, inscomp1.inscomp1_zip, inscomp1.inscomp1_form, inscomp1.inscomp1_jour, inscomp1.inscomp1_prov, inscomp1.inscomp1_typebill, inscomp1.inscomp1_perdiem, inscomp1.inscomp1_diemdt, inscomp1.inscomp1_priordiem, inscomp1.inscomp1_pcused, inscomp1.inscomp1_phybillsw, inscomp1.inscomp1_approval, inscomp1.inscomp1_psro, inscomp1.inscomp1_ask_reim, inscomp1.inscomp1_reject_days, inscomp1.inscomp1_contrgl, inscomp1.inscomp1_othargl, inscomp1.inscomp1_auto_ip, inscomp1.inscomp1_auto_op, inscomp1.inscomp1_prirate, inscomp1.inscomp1_secrate, inscomp1.inscomp1_lagdays, inscomp1.inscomp1_mul1500, inscomp1.inscomp1_waitfin, inscomp1.inscomp1_opsum, inscomp1.inscomp1_write_off, inscomp1.inscomp1_transmit, inscomp1.inscomp1_detail_bl, inscomp1.inscomp1_provname, inscomp1.inscomp1_provaddr1, inscomp1.inscomp1_provaddr2, inscomp1.inscomp1_provcity, inscomp1.inscomp1_provst, inscomp1.inscomp1_provzip, inscomp1.inscomp1_cont_perc, inscomp1.inscomp1_drg_str, inscomp1.inscomp1_drg_acps, inscomp1.inscomp1_drg_dt, inscomp1.inscomp1_ub_loc2, inscomp1.inscomp1_sub_id, inscomp1.inscomp1_bcno, inscomp1.inscomp1_taxno, inscomp1.inscomp1_mcareno, inscomp1.inscomp1_mcaidno, inscomp1.inscomp1_signature, inscomp1.inscomp1_prov2, inscomp1.inscomp1_allpay, inscomp1.inscomp1_discrate, inscomp1.inscomp1_discdt, inscomp1.inscomp1_discrate2, inscomp1.inscomp1_sumitem, inscomp1.inscomp1_bank_plan, inscomp1.inscomp1_phy_1500, inscomp1.inscomp1_labmc, inscomp1.inscomp1_orer_comb, inscomp1.inscomp1_phybillex, inscomp1.inscomp1_net_reim, inscomp1.inscomp1_ask_drg, inscomp1.inscomp1_provphone, inscomp1.inscomp1_drggroup, inscomp1.inscomp1_phyins, inscomp1.inscomp1_phyub82, inscomp1.inscomp1_mnxsnf, inscomp1.inscomp1_srcpmtcde, inscomp1.inscomp1_provname2, inscomp1.inscomp1_coll_id, inscomp1.inscomp1_diagptr, inscomp1.inscomp1_tax, inscomp1.inscomp1_type_desc, inscomp1.inscomp1_revcode, inscomp1.inscomp1_arid 
     Index Cond: ((inscomp1.inscomp1_arid = vsub.visit_arid) AND ((inscomp1.inscomp1_comp)::text = (vsub.visit_ins)::text)) 
     Filter: (now() >= (vsub.visit_disch_date + ((inscomp1.inscomp1_lagdays)::double precision * '1 day'::interval))) 
     Rows Removed by Filter: 0 
Total runtime: 985.603 ms 

Answer 1

Cela ne répond pas pourquoi, mais j'espère que cela vous aidera à comprendre. J'ai trouvé qu'une liste:

select a from t1 where x in (select y from t2) 

est très bien lorsque la liste est en faible cardinalité, mais comme la taille de la liste s'allonge, il devient moins efficace. En revanche, une semi-jointure:

select a 
from t1 
where exists (
    select null 
    from t2.x = t2.y 
    where t1. 
) 

est presque toujours efficace, pour les grandes ou petites listes. Par pure fainéantise, j'ai utilisé la liste de diffusion sur mon premier hack et je l'ai presque constamment regretté. Quand je passe à une semi-jointure, le monde est comme il se doit. Alors, pouvez-vous essayer de changer votre requête pour voir ce qui se passe?

select t.id_field, t2.field1 from table t 
LEFT JOIN table2 t2 ON t2.t_id_field = t.id_field 
WHERE exists (
    select 1 
    from table tt 
    join . . . 
    join . . . 
    where 
    t.id_field = tt.id_field and 
    <10 rows of filtering criteria> 
) 

Et pour être clair, la différence entre un semi-jointure et une jointure est que si la liste contient en répétitions, une semi-jointure ne tient pas compte des événements ultérieurs. Non seulement il ne multiplie pas les résultats de la ligne, mais il "arrête de chercher" pour chaque match.

Mais pour ce qui est de votre question principale - pouvez-vous ramener ce chiffre à ses trois premières secondes? J'en doute, parce que je soupçonne que la requête interne est d'où viennent les neuf secondes supplémentaires.

- EDIT -

Cela peut être plus de code que vous êtes prêt à traiter pour sauver neuf secondes, mais ce qui se passe lorsque vous exécutez cela?

CREATE OR REPLACE FUNCTION test() 
    RETURNS TABLE (
    id_field varchar, 
    field1 varchar 
) AS 
$BODY$ 
    DECLARE 
    id_field_list varchar[]; 
    BEGIN 
    SELECT array_agg (t.id_field) 
    into id_field_list 
    from table t 
    JOIN . . . 
    JOIN . . .  
    WHERE <10 rows of filtering criteria>; 

    return query 
    select t.id_field, t2.field1 from table t 
    LEFT JOIN table2 t2 ON t2.t_id_field = t.id_field 
    WHERE t.id_field = any(id_field_list); 
    END 
$BODY$ 
LANGUAGE plpgsql; 

et bien sûr, vous obtiendrez les résultats de la requête à partir de:

select * from test(); 

Answer 2

Une réécriture complète de votre requête:

• ne conservant que la visite et les tables de diagnostic dans la requête externe
• en déplaçant le reste des tables (qui sont seulement utilisées comme conditions) dans EXISTS() phrases
• réécrire le NULLIF(a,b) IS NULL-a > b, puisque b semble être un N/Une valeur sentinelle (je suggère -infinity pour cela, ou tout simplement NULL)
• ET changé un LEFT JOIN ... NULL à une NOT EXISTS(...) construction.
• non testé depuis que je n'ai pas la table des définitions

---

WITH vCriteria AS (
    SELECT vs.visit_id, vd.vdiag_diag 
    FROM visit vs 
    LEFT JOIN visit_diagnosis vd ON vd.vdiag_visit_key = vs.visit_id 
    WHERE EXISTS (SELECT * 
     FROM da152 da 
     WHERE da.da152_arid = vs.visit_arid 
     AND vs.visit_disch_date <= da.da152_chgdt 
     ) 
    AND EXISTS (SELECT * 
     FROM insurance_company_table1 ict 
     WHERE ict.inscomp1_comp = vs.visit_ins 
     AND ict.inscomp1_arid = vs.visit_arid 
     AND Now() >= (vs.visit_disch_date + ict.inscomp1_lagdays * INTERVAL '1 day') 
     ) 
    AND NOT EXISTS (
     SELECT * 
     FROM insurance1 ins 
     WHERE ins.is1_num = vs.visit_id AND ins.is1_ins_full = vs.visit_ins 
     AND ins.is1_bill_dt > '0001-01-01'::date 
     ) 
    AND vs.visit_mr_fdt 
     BETWEEN (now() - 50 * INTERVAL '1 day') AND (now() + 10 * INTERVAL '1 day') 
    AND vs.visit_disch_date > '0001-01-01'::date 
    AND vs.visit_servicecd_key ~ '^[0-9]+$|[FHJbKkN\\+]' = false 
    AND LEFT (vs.visit_id, 1) NOT IN ('F', 'P', 'J') 
) 
SELECT vCriteria.* FROM vCriteria 
     ;