summaryrefslogtreecommitdiffstats
path: root/doc/src/sgml/html/sql-comment.html
diff options
context:
space:
mode:
Diffstat (limited to 'doc/src/sgml/html/sql-comment.html')
-rw-r--r--doc/src/sgml/html/sql-comment.html198
1 files changed, 198 insertions, 0 deletions
diff --git a/doc/src/sgml/html/sql-comment.html b/doc/src/sgml/html/sql-comment.html
new file mode 100644
index 0000000..172a4dc
--- /dev/null
+++ b/doc/src/sgml/html/sql-comment.html
@@ -0,0 +1,198 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!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>COMMENT</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="sql-cluster.html" title="CLUSTER" /><link rel="next" href="sql-commit.html" title="COMMIT" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">COMMENT</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-cluster.html" title="CLUSTER">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-commit.html" title="COMMIT">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-COMMENT"><div class="titlepage"></div><a id="id-1.9.3.52.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">COMMENT</span></h2><p>COMMENT — define or change the comment of an object</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
+COMMENT ON
+{
+ ACCESS METHOD <em class="replaceable"><code>object_name</code></em> |
+ AGGREGATE <em class="replaceable"><code>aggregate_name</code></em> ( <em class="replaceable"><code>aggregate_signature</code></em> ) |
+ CAST (<em class="replaceable"><code>source_type</code></em> AS <em class="replaceable"><code>target_type</code></em>) |
+ COLLATION <em class="replaceable"><code>object_name</code></em> |
+ COLUMN <em class="replaceable"><code>relation_name</code></em>.<em class="replaceable"><code>column_name</code></em> |
+ CONSTRAINT <em class="replaceable"><code>constraint_name</code></em> ON <em class="replaceable"><code>table_name</code></em> |
+ CONSTRAINT <em class="replaceable"><code>constraint_name</code></em> ON DOMAIN <em class="replaceable"><code>domain_name</code></em> |
+ CONVERSION <em class="replaceable"><code>object_name</code></em> |
+ DATABASE <em class="replaceable"><code>object_name</code></em> |
+ DOMAIN <em class="replaceable"><code>object_name</code></em> |
+ EXTENSION <em class="replaceable"><code>object_name</code></em> |
+ EVENT TRIGGER <em class="replaceable"><code>object_name</code></em> |
+ FOREIGN DATA WRAPPER <em class="replaceable"><code>object_name</code></em> |
+ FOREIGN TABLE <em class="replaceable"><code>object_name</code></em> |
+ FUNCTION <em class="replaceable"><code>function_name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ] |
+ INDEX <em class="replaceable"><code>object_name</code></em> |
+ LARGE OBJECT <em class="replaceable"><code>large_object_oid</code></em> |
+ MATERIALIZED VIEW <em class="replaceable"><code>object_name</code></em> |
+ OPERATOR <em class="replaceable"><code>operator_name</code></em> (<em class="replaceable"><code>left_type</code></em>, <em class="replaceable"><code>right_type</code></em>) |
+ OPERATOR CLASS <em class="replaceable"><code>object_name</code></em> USING <em class="replaceable"><code>index_method</code></em> |
+ OPERATOR FAMILY <em class="replaceable"><code>object_name</code></em> USING <em class="replaceable"><code>index_method</code></em> |
+ POLICY <em class="replaceable"><code>policy_name</code></em> ON <em class="replaceable"><code>table_name</code></em> |
+ [ PROCEDURAL ] LANGUAGE <em class="replaceable"><code>object_name</code></em> |
+ PROCEDURE <em class="replaceable"><code>procedure_name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ] |
+ PUBLICATION <em class="replaceable"><code>object_name</code></em> |
+ ROLE <em class="replaceable"><code>object_name</code></em> |
+ ROUTINE <em class="replaceable"><code>routine_name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ] |
+ RULE <em class="replaceable"><code>rule_name</code></em> ON <em class="replaceable"><code>table_name</code></em> |
+ SCHEMA <em class="replaceable"><code>object_name</code></em> |
+ SEQUENCE <em class="replaceable"><code>object_name</code></em> |
+ SERVER <em class="replaceable"><code>object_name</code></em> |
+ STATISTICS <em class="replaceable"><code>object_name</code></em> |
+ SUBSCRIPTION <em class="replaceable"><code>object_name</code></em> |
+ TABLE <em class="replaceable"><code>object_name</code></em> |
+ TABLESPACE <em class="replaceable"><code>object_name</code></em> |
+ TEXT SEARCH CONFIGURATION <em class="replaceable"><code>object_name</code></em> |
+ TEXT SEARCH DICTIONARY <em class="replaceable"><code>object_name</code></em> |
+ TEXT SEARCH PARSER <em class="replaceable"><code>object_name</code></em> |
+ TEXT SEARCH TEMPLATE <em class="replaceable"><code>object_name</code></em> |
+ TRANSFORM FOR <em class="replaceable"><code>type_name</code></em> LANGUAGE <em class="replaceable"><code>lang_name</code></em> |
+ TRIGGER <em class="replaceable"><code>trigger_name</code></em> ON <em class="replaceable"><code>table_name</code></em> |
+ TYPE <em class="replaceable"><code>object_name</code></em> |
+ VIEW <em class="replaceable"><code>object_name</code></em>
+} IS { <em class="replaceable"><code>string_literal</code></em> | NULL }
+
+<span class="phrase">where <em class="replaceable"><code>aggregate_signature</code></em> is:</span>
+
+* |
+[ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [ , ... ] |
+[ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [ , ... ] ] ORDER BY [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [ , ... ]
+</pre></div><div class="refsect1" id="id-1.9.3.52.5"><h2>Description</h2><p>
+ <code class="command">COMMENT</code> stores a comment about a database object.
+ </p><p>
+ Only one comment string is stored for each object, so to modify a comment,
+ issue a new <code class="command">COMMENT</code> command for the same object. To remove a
+ comment, write <code class="literal">NULL</code> in place of the text string.
+ Comments are automatically dropped when their object is dropped.
+ </p><p>
+ A <code class="literal">SHARE UPDATE EXCLUSIVE</code> lock is acquired on the
+ object to be commented.
+ </p><p>
+ For most kinds of object, only the object's owner can set the comment.
+ Roles don't have owners, so the rule for <code class="literal">COMMENT ON ROLE</code> is
+ that you must be superuser to comment on a superuser role, or have the
+ <code class="literal">CREATEROLE</code> privilege to comment on non-superuser roles.
+ Likewise, access methods don't have owners either; you must be superuser
+ to comment on an access method.
+ Of course, a superuser can comment on anything.
+ </p><p>
+ Comments can be viewed using <span class="application">psql</span>'s
+ <code class="command">\d</code> family of commands.
+ Other user interfaces to retrieve comments can be built atop
+ the same built-in functions that <span class="application">psql</span> uses, namely
+ <code class="function">obj_description</code>, <code class="function">col_description</code>,
+ and <code class="function">shobj_description</code>
+ (see <a class="xref" href="functions-info.html#FUNCTIONS-INFO-COMMENT-TABLE" title="Table 9.77. Comment Information Functions">Table 9.77</a>).
+ </p></div><div class="refsect1" id="id-1.9.3.52.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>object_name</code></em><br /></span><span class="term"><em class="replaceable"><code>relation_name</code></em>.<em class="replaceable"><code>column_name</code></em><br /></span><span class="term"><em class="replaceable"><code>aggregate_name</code></em><br /></span><span class="term"><em class="replaceable"><code>constraint_name</code></em><br /></span><span class="term"><em class="replaceable"><code>function_name</code></em><br /></span><span class="term"><em class="replaceable"><code>operator_name</code></em><br /></span><span class="term"><em class="replaceable"><code>policy_name</code></em><br /></span><span class="term"><em class="replaceable"><code>procedure_name</code></em><br /></span><span class="term"><em class="replaceable"><code>routine_name</code></em><br /></span><span class="term"><em class="replaceable"><code>rule_name</code></em><br /></span><span class="term"><em class="replaceable"><code>trigger_name</code></em></span></dt><dd><p>
+ The name of the object to be commented. Names of objects that reside in
+ schemas (tables, functions, etc.) can be
+ schema-qualified. When commenting on a column,
+ <em class="replaceable"><code>relation_name</code></em> must refer
+ to a table, view, composite type, or foreign table.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>table_name</code></em><br /></span><span class="term"><em class="replaceable"><code>domain_name</code></em></span></dt><dd><p>
+ When creating a comment on a constraint, a trigger, a rule or
+ a policy these parameters specify the name of the table or domain on
+ which that object is defined.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>source_type</code></em></span></dt><dd><p>
+ The name of the source data type of the cast.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>target_type</code></em></span></dt><dd><p>
+ The name of the target data type of the cast.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>argmode</code></em></span></dt><dd><p>
+ The mode of a function, procedure, or aggregate
+ argument: <code class="literal">IN</code>, <code class="literal">OUT</code>,
+ <code class="literal">INOUT</code>, or <code class="literal">VARIADIC</code>.
+ If omitted, the default is <code class="literal">IN</code>.
+ Note that <code class="command">COMMENT</code> does not actually pay
+ any attention to <code class="literal">OUT</code> arguments, since only the input
+ arguments are needed to determine the function's identity.
+ So it is sufficient to list the <code class="literal">IN</code>, <code class="literal">INOUT</code>,
+ and <code class="literal">VARIADIC</code> arguments.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>argname</code></em></span></dt><dd><p>
+ The name of a function, procedure, or aggregate argument.
+ Note that <code class="command">COMMENT</code> does not actually pay
+ any attention to argument names, since only the argument data
+ types are needed to determine the function's identity.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>argtype</code></em></span></dt><dd><p>
+ The data type of a function, procedure, or aggregate argument.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>large_object_oid</code></em></span></dt><dd><p>
+ The OID of the large object.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>left_type</code></em><br /></span><span class="term"><em class="replaceable"><code>right_type</code></em></span></dt><dd><p>
+ The data type(s) of the operator's arguments (optionally
+ schema-qualified). Write <code class="literal">NONE</code> for the missing argument
+ of a prefix operator.
+ </p></dd><dt><span class="term"><code class="literal">PROCEDURAL</code></span></dt><dd><p>
+ This is a noise word.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>type_name</code></em></span></dt><dd><p>
+ The name of the data type of the transform.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>lang_name</code></em></span></dt><dd><p>
+ The name of the language of the transform.
+ </p></dd><dt><span class="term"><em class="replaceable"><code>string_literal</code></em></span></dt><dd><p>
+ The new comment contents, written as a string literal.
+ </p></dd><dt><span class="term"><code class="literal">NULL</code></span></dt><dd><p>
+ Write <code class="literal">NULL</code> to drop the comment.
+ </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.52.7"><h2>Notes</h2><p>
+ There is presently no security mechanism for viewing comments: any user
+ connected to a database can see all the comments for objects in
+ that database. For shared objects such as
+ databases, roles, and tablespaces, comments are stored globally so any
+ user connected to any database in the cluster can see all the comments
+ for shared objects. Therefore, don't put security-critical
+ information in comments.
+ </p></div><div class="refsect1" id="id-1.9.3.52.8"><h2>Examples</h2><p>
+ Attach a comment to the table <code class="literal">mytable</code>:
+
+</p><pre class="programlisting">
+COMMENT ON TABLE mytable IS 'This is my table.';
+</pre><p>
+
+ Remove it again:
+
+</p><pre class="programlisting">
+COMMENT ON TABLE mytable IS NULL;
+</pre><p>
+ </p><p>
+ Some more examples:
+
+</p><pre class="programlisting">
+COMMENT ON ACCESS METHOD gin IS 'GIN index access method';
+COMMENT ON AGGREGATE my_aggregate (double precision) IS 'Computes sample variance';
+COMMENT ON CAST (text AS int4) IS 'Allow casts from text to int4';
+COMMENT ON COLLATION "fr_CA" IS 'Canadian French';
+COMMENT ON COLUMN my_table.my_column IS 'Employee ID number';
+COMMENT ON CONVERSION my_conv IS 'Conversion to UTF8';
+COMMENT ON CONSTRAINT bar_col_cons ON bar IS 'Constrains column col';
+COMMENT ON CONSTRAINT dom_col_constr ON DOMAIN dom IS 'Constrains col of domain';
+COMMENT ON DATABASE my_database IS 'Development Database';
+COMMENT ON DOMAIN my_domain IS 'Email Address Domain';
+COMMENT ON EVENT TRIGGER abort_ddl IS 'Aborts all DDL commands';
+COMMENT ON EXTENSION hstore IS 'implements the hstore data type';
+COMMENT ON FOREIGN DATA WRAPPER mywrapper IS 'my foreign data wrapper';
+COMMENT ON FOREIGN TABLE my_foreign_table IS 'Employee Information in other database';
+COMMENT ON FUNCTION my_function (timestamp) IS 'Returns Roman Numeral';
+COMMENT ON INDEX my_index IS 'Enforces uniqueness on employee ID';
+COMMENT ON LANGUAGE plpython IS 'Python support for stored procedures';
+COMMENT ON LARGE OBJECT 346344 IS 'Planning document';
+COMMENT ON MATERIALIZED VIEW my_matview IS 'Summary of order history';
+COMMENT ON OPERATOR ^ (text, text) IS 'Performs intersection of two texts';
+COMMENT ON OPERATOR - (NONE, integer) IS 'Unary minus';
+COMMENT ON OPERATOR CLASS int4ops USING btree IS '4 byte integer operators for btrees';
+COMMENT ON OPERATOR FAMILY integer_ops USING btree IS 'all integer operators for btrees';
+COMMENT ON POLICY my_policy ON mytable IS 'Filter rows by users';
+COMMENT ON PROCEDURE my_proc (integer, integer) IS 'Runs a report';
+COMMENT ON PUBLICATION alltables IS 'Publishes all operations on all tables';
+COMMENT ON ROLE my_role IS 'Administration group for finance tables';
+COMMENT ON ROUTINE my_routine (integer, integer) IS 'Runs a routine (which is a function or procedure)';
+COMMENT ON RULE my_rule ON my_table IS 'Logs updates of employee records';
+COMMENT ON SCHEMA my_schema IS 'Departmental data';
+COMMENT ON SEQUENCE my_sequence IS 'Used to generate primary keys';
+COMMENT ON SERVER myserver IS 'my foreign server';
+COMMENT ON STATISTICS my_statistics IS 'Improves planner row estimations';
+COMMENT ON SUBSCRIPTION alltables IS 'Subscription for all operations on all tables';
+COMMENT ON TABLE my_schema.my_table IS 'Employee Information';
+COMMENT ON TABLESPACE my_tablespace IS 'Tablespace for indexes';
+COMMENT ON TEXT SEARCH CONFIGURATION my_config IS 'Special word filtering';
+COMMENT ON TEXT SEARCH DICTIONARY swedish IS 'Snowball stemmer for Swedish language';
+COMMENT ON TEXT SEARCH PARSER my_parser IS 'Splits text into words';
+COMMENT ON TEXT SEARCH TEMPLATE snowball IS 'Snowball stemmer';
+COMMENT ON TRANSFORM FOR hstore LANGUAGE plpython3u IS 'Transform between hstore and Python dict';
+COMMENT ON TRIGGER my_trigger ON my_table IS 'Used for RI';
+COMMENT ON TYPE complex IS 'Complex number data type';
+COMMENT ON VIEW my_view IS 'View of departmental costs';
+</pre></div><div class="refsect1" id="id-1.9.3.52.9"><h2>Compatibility</h2><p>
+ There is no <code class="command">COMMENT</code> command in the SQL standard.
+ </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-cluster.html" title="CLUSTER">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-commit.html" title="COMMIT">Next</a></td></tr><tr><td width="40%" align="left" valign="top">CLUSTER </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> COMMIT</td></tr></table></div></body></html> \ No newline at end of file