Trouble with Oracle Connect By and Date Ranges -


let's have table data ranges

create table ranges (id number, date_from date, date_to date); insert ranges values (1, to_date('01.01.2017', 'dd.mm.rrrr'), to_date('03.01.2017', 'dd.mm.rrrr')); insert ranges values (2, to_date('05.02.2017', 'dd.mm.rrrr'), to_date('08.02.2017', 'dd.mm.rrrr'));

and output should 1 row every date in these ranges

id | the_date ---------------- 1  | 01.01.2017 1  | 02.01.2017 1  | 03.01.2017 2  | 05.02.2017 2  | 06.02.2017 2  | 07.02.2017 2  | 08.02.2017

but connect gives me ora-01436 connect loop

select connect_by_root(id), trunc(date_from, 'dd') + level - 1 the_date ranges connect prior id = id , trunc(date_from, 'dd') + level - 1 <= trunc(date_to, 'dd') order id, the_date

what's wrong?

you can add call non-deterministic function, e.g.

and prior dbms_random.value not null

so becomes:

select connect_by_root(id), trunc(date_from, 'dd') + level - 1 the_date ranges connect prior id = id , prior dbms_random.value not null , trunc(date_from, 'dd') + level - 1 <= trunc(date_to, 'dd') order id, the_date;  connect_by_root(id) the_date  ------------------- ---------                   1 01-jan-17                   1 02-jan-17                   1 03-jan-17                   2 05-feb-17                   2 06-feb-17                   2 07-feb-17                   2 08-feb-17  7 rows selected.

there's explanation of why necessary in oracle community post; uses sys_guid() instead of dbms_random.value, principle same.

if you're on 11gr2 or higher use recursive subquery factoring instead:

with rcte (root_id, the_date, date_to) (   select id, date_from, date_to   ranges   union   select root_id, the_date + 1, date_to   rcte   the_date < date_to ) select root_id, the_date rcte order root_id, the_date;     root_id the_date  ---------- ---------          1 01-jan-17          1 02-jan-17          1 03-jan-17          2 05-feb-17          2 06-feb-17          2 07-feb-17          2 08-feb-17  7 rows selected.

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