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Previously, subqueries were given names only after they were planned, which makes it difficult to use information from a previous execution of the query to guide future planning. If, for example, you knew something about how you want "InitPlan 2" to be planned, you won't know whether the subquery you're currently planning will end up being "InitPlan 2" until after you've finished planning it, by which point it's too late to use the information that you had. To fix this, assign each subplan a unique name before we begin planning it. To improve consistency, use textual names for all subplans, rather than, as we did previously, a mix of numbers (such as "InitPlan 1") and names (such as "CTE foo"), and make sure that the same name is never assigned more than once. We adopt the somewhat arbitrary convention of using the type of sublink to set the plan name; for example, a query that previously had two expression sublinks shown as InitPlan 2 and InitPlan 1 will now end up named expr_1 and expr_2. Because names are assigned before rather than after planning, some of the regression test outputs show the numerical part of the name switching positions: what was previously SubPlan 2 was actually the first one encountered, but we finished planning it later. We assign names even to subqueries that aren't shown as such within the EXPLAIN output. These include subqueries that are a FROM clause item or a branch of a set operation, rather than something that will be turned into an InitPlan or SubPlan. The purpose of this is to make sure that, below the topmost query level, there's always a name for each subquery that is stable from one planning cycle to the next (assuming no changes to the query or the database schema). Author: Robert Haas <rhaas@postgresql.org> Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com> Reviewed-by: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Junwang Zhao <zhjwpku@gmail.com> Discussion: http://postgr.es/m/3641043.1758751399@sss.pgh.pa.us |
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| isolation | ||
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| ldap | ||
| locale | ||
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| perl | ||
| postmaster | ||
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PostgreSQL tests ================ This directory contains a variety of test infrastructure as well as some of the tests in PostgreSQL. Not all tests are here -- in particular, there are more in individual contrib/ modules and in src/bin. Not all these tests get run by "make check". Check src/test/Makefile to see which tests get run automatically. authentication/ Tests for authentication (but see also below) examples/ Demonstration programs for libpq that double as regression tests via "make check" isolation/ Tests for concurrent behavior at the SQL level kerberos/ Tests for Kerberos/GSSAPI authentication and encryption ldap/ Tests for LDAP-based authentication locale/ Sanity checks for locale data, encodings, etc mb/ Tests for multibyte encoding (UTF-8) support modules/ Extensions used only or mainly for test purposes, generally not suitable for installing in production databases perl/ Infrastructure for Perl-based TAP tests recovery/ Test suite for recovery and replication regress/ PostgreSQL's main regression test suite, pg_regress ssl/ Tests to exercise and verify SSL certificate handling subscription/ Tests for logical replication