PostgreSQL array error -

i new @ postgresql , create 2 table

create table hour( id integer, hour timestamp ) ;  create table activity_time( id integer, day_hours varchar[][] ) ; 

day_hours column array of combinations number of week, , id of hour table .value of column {{1,5},{2,5},{2,6}}. tried creat trigger, when delete hour hours table , in activity_time have remove in day_hours hour exist . example, if delete id=6 hour result of day_hours {{1,5},{2,5}} , or if day_hours {{3,2},{3,4},{4,2}} , if delete id=2 hour result of day_hours {{3,4}}. know how write trigger, can't write procedure execute array

with summary (     select         "unnest" (             "day_hours" [ 1 : array_length("day_hours",1)][ 1 : 1 ]:: int []         ) days,         "unnest" (             "day_hours" [ 1 : array_length("day_hours",1)][ 2 : 2 ]:: int []         ) hours             "activity_time"             "id" = 3 )   select array(select array[ s.days,s.hours]     summary s s.hours!= 2 ) 

this give error :could not find array type data type integer[] error,

the problem function array() (i mean function array() , not constructor array[]) not accept array argument. query:

select array(select array[1,2]); 

give error:

error:  not find array type data type integer[] 

the function array() accept instead set argument. use function unnest convert array in set:

select array(select unnest(array[1,2]));  -- result: --   array  --  ------- --   {1,2} 

however unnest elements of bidimensional array in 1 dimensional array. workaroud can first cast arrays text, build array of texts, cast again in text, remove quotes , cast text result in bidimensional array: query so:

with summary (     select         unnest (             day_hours [ 1 : array_length(day_hours,1)][ 1 : 1 ]:: int []         ) days,         unnest (             day_hours [ 1 : array_length(day_hours,1)][ 2 : 2 ]:: int []         ) hours             activity_time             id = 3 )  select replace(array(select  array[ s.days,s.hours]::text  -- <<< change line     summary s s.hours!= 2 )::text, '"','')::int[][] array; -- <<< change line 

this returns:

        array         ---------------------  {{1,5},{2,5},{2,6}} (1 row)