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Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.
CREATE TABLE TEST_TABLE AS
SELECT 'foo.com' AS EMAIL
1 rows affected
SELECT *
FROM TEST_TABLE
| foo.com |
SELECT regexp_matches(email, '(\w+)\.\w+$')
FROM TEST_TABLE
| regexp_matches |
|---|
| {foo} |
SELECT regexp_matches(email, '\w+\.(\w+)$')
FROM TEST_TABLE
| regexp_matches |
|---|
| {com} |
SELECT regexp_matches(email, '((\w+)\.\w+$)')
FROM TEST_TABLE
| regexp_matches |
|---|
| {foo.com,foo} |
SELECT regexp_matches(email, '(\w+\.(\w+)$)')
FROM TEST_TABLE
| regexp_matches |
|---|
| {foo.com,com} |