1
0
mirror of https://github.com/postgres/postgres.git synced 2025-09-09 13:09:39 +03:00

Add string_to_table() function.

This splits a string at occurrences of a delimiter.  It is exactly like
string_to_array() except for producing a set of values instead of an
array of values.  Thus, the relationship of these two functions is
the same as between regexp_split_to_table() and regexp_split_to_array().

Although the same results could be had from unnest(string_to_array()),
this is somewhat faster than that, and anyway it seems reasonable to
have it for symmetry with the regexp functions.

Pavel Stehule, reviewed by Peter Smith

Discussion: https://postgr.es/m/CAFj8pRD8HOpjq2TqeTBhSo_QkzjLOhXzGCpKJ4nCs7Y9SQkuPw@mail.gmail.com
This commit is contained in:
Tom Lane
2020-09-02 18:23:56 -04:00
parent fd5e3b2914
commit 66f1630680
6 changed files with 354 additions and 93 deletions

View File

@@ -544,6 +544,21 @@ select string_to_array('1,2,3,4,,6', ',');
select string_to_array('1,2,3,4,,6', ',', '');
select string_to_array('1,2,3,4,*,6', ',', '*');
select v, v is null as "is null" from string_to_table('1|2|3', '|') g(v);
select v, v is null as "is null" from string_to_table('1|2|3|', '|') g(v);
select v, v is null as "is null" from string_to_table('1||2|3||', '||') g(v);
select v, v is null as "is null" from string_to_table('1|2|3', '') g(v);
select v, v is null as "is null" from string_to_table('', '|') g(v);
select v, v is null as "is null" from string_to_table('1|2|3', NULL) g(v);
select v, v is null as "is null" from string_to_table(NULL, '|') g(v);
select v, v is null as "is null" from string_to_table('abc', '') g(v);
select v, v is null as "is null" from string_to_table('abc', '', 'abc') g(v);
select v, v is null as "is null" from string_to_table('abc', ',') g(v);
select v, v is null as "is null" from string_to_table('abc', ',', 'abc') g(v);
select v, v is null as "is null" from string_to_table('1,2,3,4,,6', ',') g(v);
select v, v is null as "is null" from string_to_table('1,2,3,4,,6', ',', '') g(v);
select v, v is null as "is null" from string_to_table('1,2,3,4,*,6', ',', '*') g(v);
select array_to_string(NULL::int4[], ',') IS NULL;
select array_to_string('{}'::int4[], ',');
select array_to_string(array[1,2,3,4,NULL,6], ',');