Query or QueryRows does not return ErrNoRows error when no record is found

[cdong8812]

Describe the bug
Query or QueryRow method does not return ErrNoRows error when using SQL left joins another table with where filter

To Reproduce
Sample SQL to reproduce the bug:

query := SELECT f.id, f.name FROM foo f LEFT JOIN bar b ON f.id = b.foo_id WHERE f.id = 123

Expected behavior
Query or QueryRow returns ErrNoRows error when no record is found

Actual behavior
Query or QueryRow returns no error when no record is found

Version

• Go: 1.22.3
• PostgreSQL: 12.2
• pgx: v5.7.2

[jackc]

First, Query will never return ErrNoRows. A query returning no rows is a perfectly valid result. Only QueryRow has the expectation of a non-empty result.

Second, the fact that your query has a left join is irrelevant to pgx. It sends the query and reads the result. The actual type of query doesn't matter. I suggest trying your query in psql. It probably is not returning what you expect.