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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 13:44:03 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 13:44:03 +0000
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+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>75.2. System Catalog Initial Data</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="system-catalog-declarations.html" title="75.1. System Catalog Declaration Rules" /><link rel="next" href="bki-format.html" title="75.3. BKI File Format" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">75.2. System Catalog Initial Data</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="system-catalog-declarations.html" title="75.1. System Catalog Declaration Rules">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="bki.html" title="Chapter 75. System Catalog Declarations and Initial Contents">Up</a></td><th width="60%" align="center">Chapter 75. System Catalog Declarations and Initial Contents</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.2 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="bki-format.html" title="75.3. BKI File Format">Next</a></td></tr></table><hr /></div><div class="sect1" id="SYSTEM-CATALOG-INITIAL-DATA"><div class="titlepage"><div><div><h2 class="title" style="clear: both">75.2. System Catalog Initial Data <a href="#SYSTEM-CATALOG-INITIAL-DATA" class="id_link">#</a></h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="system-catalog-initial-data.html#SYSTEM-CATALOG-INITIAL-DATA-FORMAT">75.2.1. Data File Format</a></span></dt><dt><span class="sect2"><a href="system-catalog-initial-data.html#SYSTEM-CATALOG-OID-ASSIGNMENT">75.2.2. OID Assignment</a></span></dt><dt><span class="sect2"><a href="system-catalog-initial-data.html#SYSTEM-CATALOG-OID-REFERENCES">75.2.3. OID Reference Lookup</a></span></dt><dt><span class="sect2"><a href="system-catalog-initial-data.html#SYSTEM-CATALOG-AUTO-ARRAY-TYPES">75.2.4. Automatic Creation of Array Types</a></span></dt><dt><span class="sect2"><a href="system-catalog-initial-data.html#SYSTEM-CATALOG-RECIPES">75.2.5. Recipes for Editing Data Files</a></span></dt></dl></div><p>
+ Each catalog that has any manually-created initial data (some do not)
+ has a corresponding <code class="literal">.dat</code> file that contains its
+ initial data in an editable format.
+ </p><div class="sect2" id="SYSTEM-CATALOG-INITIAL-DATA-FORMAT"><div class="titlepage"><div><div><h3 class="title">75.2.1. Data File Format <a href="#SYSTEM-CATALOG-INITIAL-DATA-FORMAT" class="id_link">#</a></h3></div></div></div><p>
+ Each <code class="literal">.dat</code> file contains Perl data structure literals
+ that are simply eval'd to produce an in-memory data structure consisting
+ of an array of hash references, one per catalog row.
+ A slightly modified excerpt from <code class="filename">pg_database.dat</code>
+ will demonstrate the key features:
+ </p><pre class="programlisting">
+[
+
+# A comment could appear here.
+{ oid =&gt; '1', oid_symbol =&gt; 'Template1DbOid',
+ descr =&gt; 'database\'s default template',
+ datname =&gt; 'template1', encoding =&gt; 'ENCODING',
+ datlocprovider =&gt; 'LOCALE_PROVIDER', datistemplate =&gt; 't',
+ datallowconn =&gt; 't', datconnlimit =&gt; '-1', datfrozenxid =&gt; '0',
+ datminmxid =&gt; '1', dattablespace =&gt; 'pg_default', datcollate =&gt; 'LC_COLLATE',
+ datctype =&gt; 'LC_CTYPE', daticulocale =&gt; 'ICU_LOCALE', datacl =&gt; '_null_' },
+
+]
+</pre><p>
+ Points to note:
+ </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
+ The overall file layout is: open square bracket, one or more sets of
+ curly braces each of which represents a catalog row, close square
+ bracket. Write a comma after each closing curly brace.
+ </p></li><li class="listitem"><p>
+ Within each catalog row, write comma-separated
+ <em class="replaceable"><code>key</code></em> <code class="literal">=&gt;</code>
+ <em class="replaceable"><code>value</code></em> pairs. The
+ allowed <em class="replaceable"><code>key</code></em>s are the names of the catalog's
+ columns, plus the metadata keys <code class="literal">oid</code>,
+ <code class="literal">oid_symbol</code>,
+ <code class="literal">array_type_oid</code>, and <code class="literal">descr</code>.
+ (The use of <code class="literal">oid</code> and <code class="literal">oid_symbol</code>
+ is described in <a class="xref" href="system-catalog-initial-data.html#SYSTEM-CATALOG-OID-ASSIGNMENT" title="75.2.2. OID Assignment">Section 75.2.2</a> below,
+ while <code class="literal">array_type_oid</code> is described in
+ <a class="xref" href="system-catalog-initial-data.html#SYSTEM-CATALOG-AUTO-ARRAY-TYPES" title="75.2.4. Automatic Creation of Array Types">Section 75.2.4</a>.
+ <code class="literal">descr</code> supplies a description string for the object,
+ which will be inserted into <code class="structname">pg_description</code>
+ or <code class="structname">pg_shdescription</code> as appropriate.)
+ While the metadata keys are optional, the catalog's defined columns
+ must all be provided, except when the catalog's <code class="literal">.h</code>
+ file specifies a default value for the column.
+ (In the example above, the <code class="structfield">datdba</code> field has
+ been omitted because <code class="filename">pg_database.h</code> supplies a
+ suitable default value for it.)
+ </p></li><li class="listitem"><p>
+ All values must be single-quoted. Escape single quotes used within a
+ value with a backslash. Backslashes meant as data can, but need not,
+ be doubled; this follows Perl's rules for simple quoted literals.
+ Note that backslashes appearing as data will be treated as escapes by
+ the bootstrap scanner, according to the same rules as for escape string
+ constants (see <a class="xref" href="sql-syntax-lexical.html#SQL-SYNTAX-STRINGS-ESCAPE" title="4.1.2.2. String Constants with C-Style Escapes">Section 4.1.2.2</a>); for
+ example <code class="literal">\t</code> converts to a tab character. If you
+ actually want a backslash in the final value, you will need to write
+ four of them: Perl strips two, leaving <code class="literal">\\</code> for the
+ bootstrap scanner to see.
+ </p></li><li class="listitem"><p>
+ Null values are represented by <code class="literal">_null_</code>.
+ (Note that there is no way to create a value that is just that
+ string.)
+ </p></li><li class="listitem"><p>
+ Comments are preceded by <code class="literal">#</code>, and must be on their
+ own lines.
+ </p></li><li class="listitem"><p>
+ Field values that are OIDs of other catalog entries should be
+ represented by symbolic names rather than actual numeric OIDs.
+ (In the example above, <code class="structfield">dattablespace</code>
+ contains such a reference.)
+ This is described in <a class="xref" href="system-catalog-initial-data.html#SYSTEM-CATALOG-OID-REFERENCES" title="75.2.3. OID Reference Lookup">Section 75.2.3</a>
+ below.
+ </p></li><li class="listitem"><p>
+ Since hashes are unordered data structures, field order and line
+ layout aren't semantically significant. However, to maintain a
+ consistent appearance, we set a few rules that are applied by the
+ formatting script <code class="filename">reformat_dat_file.pl</code>:
+
+ </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; "><li class="listitem"><p>
+ Within each pair of curly braces, the metadata
+ fields <code class="literal">oid</code>, <code class="literal">oid_symbol</code>,
+ <code class="literal">array_type_oid</code>, and <code class="literal">descr</code>
+ (if present) come first, in that order, then the catalog's own
+ fields appear in their defined order.
+ </p></li><li class="listitem"><p>
+ Newlines are inserted between fields as needed to limit line length
+ to 80 characters, if possible. A newline is also inserted between
+ the metadata fields and the regular fields.
+ </p></li><li class="listitem"><p>
+ If the catalog's <code class="literal">.h</code> file specifies a default
+ value for a column, and a data entry has that same
+ value, <code class="filename">reformat_dat_file.pl</code> will omit it from
+ the data file. This keeps the data representation compact.
+ </p></li><li class="listitem"><p>
+ <code class="filename">reformat_dat_file.pl</code> preserves blank lines
+ and comment lines as-is.
+ </p></li></ul></div><p>
+
+ It's recommended to run <code class="filename">reformat_dat_file.pl</code>
+ before submitting catalog data patches. For convenience, you can
+ simply change to <code class="filename">src/include/catalog/</code> and
+ run <code class="literal">make reformat-dat-files</code>.
+ </p></li><li class="listitem"><p>
+ If you want to add a new method of making the data representation
+ smaller, you must implement it
+ in <code class="filename">reformat_dat_file.pl</code> and also
+ teach <code class="function">Catalog::ParseData()</code> how to expand the
+ data back into the full representation.
+ </p></li></ul></div></div><div class="sect2" id="SYSTEM-CATALOG-OID-ASSIGNMENT"><div class="titlepage"><div><div><h3 class="title">75.2.2. OID Assignment <a href="#SYSTEM-CATALOG-OID-ASSIGNMENT" class="id_link">#</a></h3></div></div></div><p>
+ A catalog row appearing in the initial data can be given a
+ manually-assigned OID by writing an <code class="literal">oid
+ =&gt; <em class="replaceable"><code>nnnn</code></em></code> metadata field.
+ Furthermore, if an OID is assigned, a C macro for that OID can be
+ created by writing an <code class="literal">oid_symbol
+ =&gt; <em class="replaceable"><code>name</code></em></code> metadata field.
+ </p><p>
+ Pre-loaded catalog rows must have preassigned OIDs if there are OID
+ references to them in other pre-loaded rows. A preassigned OID is
+ also needed if the row's OID must be referenced from C code.
+ If neither case applies, the <code class="literal">oid</code> metadata field can
+ be omitted, in which case the bootstrap code assigns an OID
+ automatically.
+ In practice we usually preassign OIDs for all or none of the pre-loaded
+ rows in a given catalog, even if only some of them are actually
+ cross-referenced.
+ </p><p>
+ Writing the actual numeric value of any OID in C code is considered
+ very bad form; always use a macro, instead. Direct references
+ to <code class="structname">pg_proc</code> OIDs are common enough that there's
+ a special mechanism to create the necessary macros automatically;
+ see <code class="filename">src/backend/utils/Gen_fmgrtab.pl</code>. Similarly
+ — but, for historical reasons, not done the same way —
+ there's an automatic method for creating macros
+ for <code class="structname">pg_type</code>
+ OIDs. <code class="literal">oid_symbol</code> entries are therefore not
+ necessary in those two catalogs. Likewise, macros for
+ the <code class="structname">pg_class</code> OIDs of system catalogs and
+ indexes are set up automatically. For all other system catalogs, you
+ have to manually specify any macros you need
+ via <code class="literal">oid_symbol</code> entries.
+ </p><p>
+ To find an available OID for a new pre-loaded row, run the
+ script <code class="filename">src/include/catalog/unused_oids</code>.
+ It prints inclusive ranges of unused OIDs (e.g., the output
+ line <code class="literal">45-900</code> means OIDs 45 through 900 have not been
+ allocated yet). Currently, OIDs 1–9999 are reserved for manual
+ assignment; the <code class="filename">unused_oids</code> script simply looks
+ through the catalog headers and <code class="filename">.dat</code> files
+ to see which ones do not appear. You can also use
+ the <code class="filename">duplicate_oids</code> script to check for mistakes.
+ (<code class="filename">genbki.pl</code> will assign OIDs for any rows that
+ didn't get one hand-assigned to them, and it will also detect duplicate
+ OIDs at compile time.)
+ </p><p>
+ When choosing OIDs for a patch that is not expected to be committed
+ immediately, best practice is to use a group of more-or-less
+ consecutive OIDs starting with some random choice in the range
+ 8000—9999. This minimizes the risk of OID collisions with other
+ patches being developed concurrently. To keep the 8000—9999
+ range free for development purposes, after a patch has been committed
+ to the master git repository its OIDs should be renumbered into
+ available space below that range. Typically, this will be done
+ near the end of each development cycle, moving all OIDs consumed by
+ patches committed in that cycle at the same time. The script
+ <code class="filename">renumber_oids.pl</code> can be used for this purpose.
+ If an uncommitted patch is found to have OID conflicts with some
+ recently-committed patch, <code class="filename">renumber_oids.pl</code> may
+ also be useful for recovering from that situation.
+ </p><p>
+ Because of this convention of possibly renumbering OIDs assigned by
+ patches, the OIDs assigned by a patch should not be considered stable
+ until the patch has been included in an official release. We do not
+ change manually-assigned object OIDs once released, however, as that
+ would create assorted compatibility problems.
+ </p><p>
+ If <code class="filename">genbki.pl</code> needs to assign an OID to a catalog
+ entry that does not have a manually-assigned OID, it will use a value in
+ the range 10000—11999. The server's OID counter is set to 10000
+ at the start of a bootstrap run, so that any objects created on-the-fly
+ during bootstrap processing also receive OIDs in this range. (The
+ usual OID assignment mechanism takes care of preventing any conflicts.)
+ </p><p>
+ Objects with OIDs below <code class="symbol">FirstUnpinnedObjectId</code> (12000)
+ are considered <span class="quote">“<span class="quote">pinned</span>”</span>, preventing them from being
+ deleted. (There are a small number of exceptions, which are
+ hard-wired into <code class="function">IsPinnedObject()</code>.)
+ <span class="application">initdb</span> forces the OID counter up
+ to <code class="symbol">FirstUnpinnedObjectId</code> as soon as it's ready to
+ create unpinned objects. Thus objects created during the later phases
+ of <span class="application">initdb</span>, such as objects created while
+ running the <code class="filename">information_schema.sql</code> script, will
+ not be pinned, while all objects known
+ to <code class="filename">genbki.pl</code> will be.
+ </p><p>
+ OIDs assigned during normal database operation are constrained to be
+ 16384 or higher. This ensures that the range 10000—16383 is free
+ for OIDs assigned automatically by <code class="filename">genbki.pl</code> or
+ during <span class="application">initdb</span>. These
+ automatically-assigned OIDs are not considered stable, and may change
+ from one installation to another.
+ </p></div><div class="sect2" id="SYSTEM-CATALOG-OID-REFERENCES"><div class="titlepage"><div><div><h3 class="title">75.2.3. OID Reference Lookup <a href="#SYSTEM-CATALOG-OID-REFERENCES" class="id_link">#</a></h3></div></div></div><p>
+ In principle, cross-references from one initial catalog row to another
+ could be written just by writing the preassigned OID of the referenced
+ row in the referencing field. However, that is against project
+ policy, because it is error-prone, hard to read, and subject to
+ breakage if a newly-assigned OID is renumbered. Therefore
+ <code class="filename">genbki.pl</code> provides mechanisms to write
+ symbolic references instead.
+ The rules are as follows:
+ </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
+ Use of symbolic references is enabled in a particular catalog column
+ by attaching <code class="literal">BKI_LOOKUP(<em class="replaceable"><code>lookuprule</code></em>)</code>
+ to the column's definition, where <em class="replaceable"><code>lookuprule</code></em>
+ is the name of the referenced catalog, e.g., <code class="literal">pg_proc</code>.
+ <code class="literal">BKI_LOOKUP</code> can be attached to columns of
+ type <code class="type">Oid</code>, <code class="type">regproc</code>, <code class="type">oidvector</code>,
+ or <code class="type">Oid[]</code>; in the latter two cases it implies performing a
+ lookup on each element of the array.
+ </p></li><li class="listitem"><p>
+ It's also permissible to attach <code class="literal">BKI_LOOKUP(encoding)</code>
+ to integer columns to reference character set encodings, which are
+ not currently represented as catalog OIDs, but have a set of values
+ known to <code class="filename">genbki.pl</code>.
+ </p></li><li class="listitem"><p>
+ In some catalog columns, it's allowed for entries to be zero instead
+ of a valid reference. If this is allowed, write
+ <code class="literal">BKI_LOOKUP_OPT</code> instead
+ of <code class="literal">BKI_LOOKUP</code>. Then you can
+ write <code class="literal">0</code> for an entry. (If the column is
+ declared <code class="type">regproc</code>, you can optionally
+ write <code class="literal">-</code> instead of <code class="literal">0</code>.)
+ Except for this special case, all entries in
+ a <code class="literal">BKI_LOOKUP</code> column must be symbolic references.
+ <code class="filename">genbki.pl</code> will warn about unrecognized names.
+ </p></li><li class="listitem"><p>
+ Most kinds of catalog objects are simply referenced by their names.
+ Note that type names must exactly match the
+ referenced <code class="structname">pg_type</code>
+ entry's <code class="structfield">typname</code>; you do not get to use
+ any aliases such as <code class="literal">integer</code>
+ for <code class="literal">int4</code>.
+ </p></li><li class="listitem"><p>
+ A function can be represented by
+ its <code class="structfield">proname</code>, if that is unique among
+ the <code class="filename">pg_proc.dat</code> entries (this works like regproc
+ input). Otherwise, write it
+ as <em class="replaceable"><code>proname(argtypename,argtypename,...)</code></em>,
+ like regprocedure. The argument type names must be spelled exactly as
+ they are in the <code class="filename">pg_proc.dat</code> entry's
+ <code class="structfield">proargtypes</code> field. Do not insert any
+ spaces.
+ </p></li><li class="listitem"><p>
+ Operators are represented
+ by <em class="replaceable"><code>oprname(lefttype,righttype)</code></em>,
+ writing the type names exactly as they appear in
+ the <code class="filename">pg_operator.dat</code>
+ entry's <code class="structfield">oprleft</code>
+ and <code class="structfield">oprright</code> fields.
+ (Write <code class="literal">0</code> for the omitted operand of a unary
+ operator.)
+ </p></li><li class="listitem"><p>
+ The names of opclasses and opfamilies are only unique within an
+ access method, so they are represented
+ by <em class="replaceable"><code>access_method_name</code></em><code class="literal">/</code><em class="replaceable"><code>object_name</code></em>.
+ </p></li><li class="listitem"><p>
+ In none of these cases is there any provision for
+ schema-qualification; all objects created during bootstrap are
+ expected to be in the <code class="literal">pg_catalog</code> schema.
+ </p></li></ul></div><p>
+ <code class="filename">genbki.pl</code> resolves all symbolic references while it
+ runs, and puts simple numeric OIDs into the emitted BKI file. There is
+ therefore no need for the bootstrap backend to deal with symbolic
+ references.
+ </p><p>
+ It's desirable to mark OID reference columns
+ with <code class="literal">BKI_LOOKUP</code> or <code class="literal">BKI_LOOKUP_OPT</code>
+ even if the catalog has no initial data that requires lookup. This
+ allows <code class="filename">genbki.pl</code> to record the foreign key
+ relationships that exist in the system catalogs. That information is
+ used in the regression tests to check for incorrect entries. See also
+ the macros <code class="literal">DECLARE_FOREIGN_KEY</code>,
+ <code class="literal">DECLARE_FOREIGN_KEY_OPT</code>,
+ <code class="literal">DECLARE_ARRAY_FOREIGN_KEY</code>,
+ and <code class="literal">DECLARE_ARRAY_FOREIGN_KEY_OPT</code>, which are
+ used to declare foreign key relationships that are too complex
+ for <code class="literal">BKI_LOOKUP</code> (typically, multi-column foreign
+ keys).
+ </p></div><div class="sect2" id="SYSTEM-CATALOG-AUTO-ARRAY-TYPES"><div class="titlepage"><div><div><h3 class="title">75.2.4. Automatic Creation of Array Types <a href="#SYSTEM-CATALOG-AUTO-ARRAY-TYPES" class="id_link">#</a></h3></div></div></div><p>
+ Most scalar data types should have a corresponding array type (that is,
+ a standard varlena array type whose element type is the scalar type, and
+ which is referenced by the <code class="structfield">typarray</code> field of
+ the scalar type's <code class="structname">pg_type</code>
+ entry). <code class="filename">genbki.pl</code> is able to generate
+ the <code class="structname">pg_type</code> entry for the array type
+ automatically in most cases.
+ </p><p>
+ To use this facility, just write an <code class="literal">array_type_oid
+ =&gt; <em class="replaceable"><code>nnnn</code></em></code> metadata field in the
+ scalar type's <code class="structname">pg_type</code> entry, specifying the OID
+ to use for the array type. You may then omit
+ the <code class="structfield">typarray</code> field, since it will be filled
+ automatically with that OID.
+ </p><p>
+ The generated array type's name is the scalar type's name with an
+ underscore prepended. The array entry's other fields are filled from
+ <code class="literal">BKI_ARRAY_DEFAULT(<em class="replaceable"><code>value</code></em>)</code>
+ annotations in <code class="filename">pg_type.h</code>, or if there isn't one,
+ copied from the scalar type. (There's also a special case
+ for <code class="structfield">typalign</code>.) Then
+ the <code class="structfield">typelem</code>
+ and <code class="structfield">typarray</code> fields of the two entries are
+ set to cross-reference each other.
+ </p></div><div class="sect2" id="SYSTEM-CATALOG-RECIPES"><div class="titlepage"><div><div><h3 class="title">75.2.5. Recipes for Editing Data Files <a href="#SYSTEM-CATALOG-RECIPES" class="id_link">#</a></h3></div></div></div><p>
+ Here are some suggestions about the easiest ways to perform common tasks
+ when updating catalog data files.
+ </p><p><strong>Add a new column with a default to a catalog: </strong>
+ Add the column to the header file with
+ a <code class="literal">BKI_DEFAULT(<em class="replaceable"><code>value</code></em>)</code>
+ annotation. The data file need only be adjusted by adding the field
+ in existing rows where a non-default value is needed.
+ </p><p><strong>Add a default value to an existing column that doesn't have
+ one: </strong>
+ Add a <code class="literal">BKI_DEFAULT</code> annotation to the header file,
+ then run <code class="literal">make reformat-dat-files</code> to remove
+ now-redundant field entries.
+ </p><p><strong>Remove a column, whether it has a default or not: </strong>
+ Remove the column from the header, then run <code class="literal">make
+ reformat-dat-files</code> to remove now-useless field entries.
+ </p><p><strong>Change or remove an existing default value: </strong>
+ You cannot simply change the header file, since that will cause the
+ current data to be interpreted incorrectly. First run <code class="literal">make
+ expand-dat-files</code> to rewrite the data files with all
+ default values inserted explicitly, then change or remove
+ the <code class="literal">BKI_DEFAULT</code> annotation, then run <code class="literal">make
+ reformat-dat-files</code> to remove superfluous fields again.
+ </p><p><strong>Ad-hoc bulk editing: </strong>
+ <code class="filename">reformat_dat_file.pl</code> can be adapted to perform
+ many kinds of bulk changes. Look for its block comments showing where
+ one-off code can be inserted. In the following example, we are going
+ to consolidate two Boolean fields in <code class="structname">pg_proc</code>
+ into a char field:
+
+ </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
+ Add the new column, with a default,
+ to <code class="filename">pg_proc.h</code>:
+</p><pre class="programlisting">
++ /* see PROKIND_ categories below */
++ char prokind BKI_DEFAULT(f);
+</pre><p>
+ </p></li><li class="listitem"><p>
+ Create a new script based on <code class="filename">reformat_dat_file.pl</code>
+ to insert appropriate values on-the-fly:
+</p><pre class="programlisting">
+- # At this point we have the full row in memory as a hash
+- # and can do any operations we want. As written, it only
+- # removes default values, but this script can be adapted to
+- # do one-off bulk-editing.
++ # One-off change to migrate to prokind
++ # Default has already been filled in by now, so change to other
++ # values as appropriate
++ if ($values{proisagg} eq 't')
++ {
++ $values{prokind} = 'a';
++ }
++ elsif ($values{proiswindow} eq 't')
++ {
++ $values{prokind} = 'w';
++ }
+</pre><p>
+ </p></li><li class="listitem"><p>
+ Run the new script:
+</p><pre class="programlisting">
+$ cd src/include/catalog
+$ perl rewrite_dat_with_prokind.pl pg_proc.dat
+</pre><p>
+ At this point <code class="filename">pg_proc.dat</code> has all three
+ columns, <code class="structfield">prokind</code>,
+ <code class="structfield">proisagg</code>,
+ and <code class="structfield">proiswindow</code>, though they will appear
+ only in rows where they have non-default values.
+ </p></li><li class="listitem"><p>
+ Remove the old columns from <code class="filename">pg_proc.h</code>:
+</p><pre class="programlisting">
+- /* is it an aggregate? */
+- bool proisagg BKI_DEFAULT(f);
+-
+- /* is it a window function? */
+- bool proiswindow BKI_DEFAULT(f);
+</pre><p>
+ </p></li><li class="listitem"><p>
+ Finally, run <code class="literal">make reformat-dat-files</code> to remove
+ the useless old entries from <code class="filename">pg_proc.dat</code>.
+ </p></li></ol></div><p>
+
+ For further examples of scripts used for bulk editing, see
+ <code class="filename">convert_oid2name.pl</code>
+ and <code class="filename">remove_pg_type_oid_symbols.pl</code> attached to this
+ message:
+ <a class="ulink" href="https://www.postgresql.org/message-id/CAJVSVGVX8gXnPm+Xa=DxR7kFYprcQ1tNcCT5D0O3ShfnM6jehA@mail.gmail.com" target="_top">https://www.postgresql.org/message-id/CAJVSVGVX8gXnPm+Xa=DxR7kFYprcQ1tNcCT5D0O3ShfnM6jehA@mail.gmail.com</a>
+ </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="system-catalog-declarations.html" title="75.1. System Catalog Declaration Rules">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="bki.html" title="Chapter 75. System Catalog Declarations and Initial Contents">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="bki-format.html" title="75.3. BKI File Format">Next</a></td></tr><tr><td width="40%" align="left" valign="top">75.1. System Catalog Declaration Rules </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.2 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 75.3. <acronym class="acronym">BKI</acronym> File Format</td></tr></table></div></body></html> \ No newline at end of file