sqlite - Group by regex count - 


id 1001 2001 2002 3001 3002 3003

how group id column first digit 1, 2, 3? mean below:

select count(*) my_tbl group expr_id_1st_digit;  count(*) 1 2 3

try this:

select count(*)    (select substr(id, 1, 1) mygroup            table1)  group  mygroup

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