PostgreSQL/Array/Array Upper

Upper and lower bound of a specified array dimension

postgres=#
postgres=# CREATE TABLE sal_emp (
postgres(#    name            text,
postgres(#    pay_by_quarter  integer[],
postgres(#    schedule        text[][]
postgres(# );
CREATE TABLE
postgres=#
postgres=# INSERT INTO sal_emp
postgres-#    VALUES ("Bill",
postgres(#    ARRAY[10000, 10000, 10000, 10000],
postgres(#    ARRAY[["meeting", "lunch"], ["training", "presentation"]]);
INSERT 0 1
postgres=#
postgres=# INSERT INTO sal_emp
postgres-#    VALUES ("Carol",
postgres(#    ARRAY[20000, 25000, 25000, 25000],
postgres(#    ARRAY[["breakfast", "consulting"], ["meeting", "lunch"]]);
INSERT 0 1
postgres=#
postgres=# SELECT * FROM sal_emp;
 name  |      pay_by_quarter       |                 schedule
-------+---------------------------+-------------------------------------------
 Bill  | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
 Carol | {20000,25000,25000,25000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=# -- Upper and lower bound of a specified array dimension
postgres=#
postgres=# SELECT array_upper(schedule, 1) FROM sal_emp WHERE name = "Carol";
 array_upper
-------------
           2
(1 row)
postgres=#
postgres=#
postgres=# drop table sal_emp;
DROP TABLE
postgres=#
postgres=#