sql - MySQL - join in one query -


i have 2 tables:

leads

 |lead_id|name| |      1|   a| |      2|   b| |      3|   c| 
lead_phases
 |phase_id|phase_lead_fk|phase_sort|phase_status| |       1|            1|         1|           1| |       2|            1|         2|           0| |       3|            2|         3|           1| |       4|            2|         1|           0| |       5|            2|         2|           0| |       6|            3|         1|           0| |       7|            3|         2|           1| 

i have write 1 query show joined table grouped lead_id , highest value of column phase_sort.

the result receive:

 |lead_id|name|phase_id|phase_sort|phase_status| |      1|   a|       2|         2|           0| |      2|   b|       3|         3|           1| |      3|   c|       7|         7|           1| 

my query:

 select phase_id,phase_lead_fk,phase_sort,phase_status leads left join lead_phases on lead_id=phase_lead_fk group lead_id  

you need in 2 steps

select  phase_lead_fk, max(phase_sort)    lead_phases group phase_lead_fk 

this return hights sort value each lead; can use result filter joining 2 original tables

select  *    leads t1 join    lead_phases t2 on      t1.lead_id = t2.phase_lead_fk join    (             select  phase_lead_fk, max(phase_sort) max_phase_sort                lead_phases             group phase_lead_fk         ) t3 on      t2.phase_lead_fk = t3.phase_lead_fk ,         t2.phase_sort = t3.max_phase_sort 

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