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7bddca3450
equality checks it applies, instead of a random dependence on whatever operators might be named "=". The equality operators will now be selected from the opfamily of the unique index that the FK constraint depends on to enforce uniqueness of the referenced columns; therefore they are certain to be consistent with that index's notion of equality. Among other things this should fix the problem noted awhile back that pg_dump may fail for foreign-key constraints on user-defined types when the required operators aren't in the search path. This also means that the former warning condition about "foreign key constraint will require costly sequential scans" is gone: if the comparison condition isn't indexable then we'll reject the constraint entirely. All per past discussions. Along the way, make the RI triggers look into pg_constraint for their information, instead of using pg_trigger.tgargs; and get rid of the always error-prone fixed-size string buffers in ri_triggers.c in favor of building up the RI queries in StringInfo buffers. initdb forced due to columns added to pg_constraint and pg_trigger.
58 lines
2.6 KiB
C
58 lines
2.6 KiB
C
/*-------------------------------------------------------------------------
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*
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* catversion.h
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* "Catalog version number" for PostgreSQL.
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*
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* The catalog version number is used to flag incompatible changes in
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* the PostgreSQL system catalogs. Whenever anyone changes the format of
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* a system catalog relation, or adds, deletes, or modifies standard
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* catalog entries in such a way that an updated backend wouldn't work
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* with an old database (or vice versa), the catalog version number
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* should be changed. The version number stored in pg_control by initdb
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* is checked against the version number compiled into the backend at
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* startup time, so that a backend can refuse to run in an incompatible
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* database.
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*
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* The point of this feature is to provide a finer grain of compatibility
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* checking than is possible from looking at the major version number
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* stored in PG_VERSION. It shouldn't matter to end users, but during
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* development cycles we usually make quite a few incompatible changes
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* to the contents of the system catalogs, and we don't want to bump the
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* major version number for each one. What we can do instead is bump
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* this internal version number. This should save some grief for
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* developers who might otherwise waste time tracking down "bugs" that
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* are really just code-vs-database incompatibilities.
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*
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* The rule for developers is: if you commit a change that requires
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* an initdb, you should update the catalog version number (as well as
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* notifying the pghackers mailing list, which has been the informal
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* practice for a long time).
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*
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* The catalog version number is placed here since modifying files in
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* include/catalog is the most common kind of initdb-forcing change.
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* But it could be used to protect any kind of incompatible change in
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* database contents or layout, such as altering tuple headers.
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*
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*
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* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.384 2007/02/14 01:58:58 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#ifndef CATVERSION_H
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#define CATVERSION_H
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/*
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* We could use anything we wanted for version numbers, but I recommend
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* following the "YYYYMMDDN" style often used for DNS zone serial numbers.
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* YYYYMMDD are the date of the change, and N is the number of the change
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* on that day. (Hopefully we'll never commit ten independent sets of
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* catalog changes on the same day...)
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*/
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/* yyyymmddN */
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#define CATALOG_VERSION_NO 200702131
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#endif
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