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<?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>37.6. attributes</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="infoschema-applicable-roles.html" title="37.5. applicable_roles" /><link rel="next" href="infoschema-character-sets.html" title="37.7. character_sets" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">37.6. <code class="literal">attributes</code></th></tr><tr><td width="10%" align="left"><a accesskey="p" href="infoschema-applicable-roles.html" title="37.5. applicable_roles">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="information-schema.html" title="Chapter 37. The Information Schema">Up</a></td><th width="60%" align="center">Chapter 37. The Information Schema</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="infoschema-character-sets.html" title="37.7. character_sets">Next</a></td></tr></table><hr /></div><div class="sect1" id="INFOSCHEMA-ATTRIBUTES"><div class="titlepage"><div><div><h2 class="title" style="clear: both">37.6. <code class="literal">attributes</code> <a href="#INFOSCHEMA-ATTRIBUTES" class="id_link">#</a></h2></div></div></div><p> The view <code class="literal">attributes</code> contains information about the attributes of composite data types defined in the database. (Note that the view does not give information about table columns, which are sometimes called attributes in PostgreSQL contexts.) Only those attributes are shown that the current user has access to (by way of being the owner of or having some privilege on the type). </p><div class="table" id="id-1.7.6.10.3"><p class="title"><strong>Table 37.4. <code class="structname">attributes</code> Columns</strong></p><div class="table-contents"><table class="table" summary="attributes Columns" border="1"><colgroup><col /></colgroup><thead><tr><th class="catalog_table_entry"><p class="column_definition"> Column Type </p> <p> Description </p></th></tr></thead><tbody><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">udt_catalog</code> <code class="type">sql_identifier</code> </p> <p> Name of the database containing the data type (always the current database) </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">udt_schema</code> <code class="type">sql_identifier</code> </p> <p> Name of the schema containing the data type </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">udt_name</code> <code class="type">sql_identifier</code> </p> <p> Name of the data type </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">attribute_name</code> <code class="type">sql_identifier</code> </p> <p> Name of the attribute </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">ordinal_position</code> <code class="type">cardinal_number</code> </p> <p> Ordinal position of the attribute within the data type (count starts at 1) </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">attribute_default</code> <code class="type">character_data</code> </p> <p> Default expression of the attribute </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">is_nullable</code> <code class="type">yes_or_no</code> </p> <p> <code class="literal">YES</code> if the attribute is possibly nullable, <code class="literal">NO</code> if it is known not nullable. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">data_type</code> <code class="type">character_data</code> </p> <p> Data type of the attribute, if it is a built-in type, or <code class="literal">ARRAY</code> if it is some array (in that case, see the view <code class="literal">element_types</code>), else <code class="literal">USER-DEFINED</code> (in that case, the type is identified in <code class="literal">attribute_udt_name</code> and associated columns). </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">character_maximum_length</code> <code class="type">cardinal_number</code> </p> <p> If <code class="literal">data_type</code> identifies a character or bit string type, the declared maximum length; null for all other data types or if no maximum length was declared. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">character_octet_length</code> <code class="type">cardinal_number</code> </p> <p> If <code class="literal">data_type</code> identifies a character type, the maximum possible length in octets (bytes) of a datum; null for all other data types. The maximum octet length depends on the declared character maximum length (see above) and the server encoding. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">character_set_catalog</code> <code class="type">sql_identifier</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">character_set_schema</code> <code class="type">sql_identifier</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">character_set_name</code> <code class="type">sql_identifier</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">collation_catalog</code> <code class="type">sql_identifier</code> </p> <p> Name of the database containing the collation of the attribute (always the current database), null if default or the data type of the attribute is not collatable </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">collation_schema</code> <code class="type">sql_identifier</code> </p> <p> Name of the schema containing the collation of the attribute, null if default or the data type of the attribute is not collatable </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">collation_name</code> <code class="type">sql_identifier</code> </p> <p> Name of the collation of the attribute, null if default or the data type of the attribute is not collatable </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">numeric_precision</code> <code class="type">cardinal_number</code> </p> <p> If <code class="literal">data_type</code> identifies a numeric type, this column contains the (declared or implicit) precision of the type for this attribute. The precision indicates the number of significant digits. It can be expressed in decimal (base 10) or binary (base 2) terms, as specified in the column <code class="literal">numeric_precision_radix</code>. For all other data types, this column is null. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">numeric_precision_radix</code> <code class="type">cardinal_number</code> </p> <p> If <code class="literal">data_type</code> identifies a numeric type, this column indicates in which base the values in the columns <code class="literal">numeric_precision</code> and <code class="literal">numeric_scale</code> are expressed. The value is either 2 or 10. For all other data types, this column is null. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">numeric_scale</code> <code class="type">cardinal_number</code> </p> <p> If <code class="literal">data_type</code> identifies an exact numeric type, this column contains the (declared or implicit) scale of the type for this attribute. The scale indicates the number of significant digits to the right of the decimal point. It can be expressed in decimal (base 10) or binary (base 2) terms, as specified in the column <code class="literal">numeric_precision_radix</code>. For all other data types, this column is null. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">datetime_precision</code> <code class="type">cardinal_number</code> </p> <p> If <code class="literal">data_type</code> identifies a date, time, timestamp, or interval type, this column contains the (declared or implicit) fractional seconds precision of the type for this attribute, that is, the number of decimal digits maintained following the decimal point in the seconds value. For all other data types, this column is null. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">interval_type</code> <code class="type">character_data</code> </p> <p> If <code class="literal">data_type</code> identifies an interval type, this column contains the specification which fields the intervals include for this attribute, e.g., <code class="literal">YEAR TO MONTH</code>, <code class="literal">DAY TO SECOND</code>, etc. If no field restrictions were specified (that is, the interval accepts all fields), and for all other data types, this field is null. </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">interval_precision</code> <code class="type">cardinal_number</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> (see <code class="literal">datetime_precision</code> for the fractional seconds precision of interval type attributes) </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">attribute_udt_catalog</code> <code class="type">sql_identifier</code> </p> <p> Name of the database that the attribute data type is defined in (always the current database) </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">attribute_udt_schema</code> <code class="type">sql_identifier</code> </p> <p> Name of the schema that the attribute data type is defined in </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">attribute_udt_name</code> <code class="type">sql_identifier</code> </p> <p> Name of the attribute data type </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">scope_catalog</code> <code class="type">sql_identifier</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">scope_schema</code> <code class="type">sql_identifier</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">scope_name</code> <code class="type">sql_identifier</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">maximum_cardinality</code> <code class="type">cardinal_number</code> </p> <p> Always null, because arrays always have unlimited maximum cardinality in <span class="productname">PostgreSQL</span> </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">dtd_identifier</code> <code class="type">sql_identifier</code> </p> <p> An identifier of the data type descriptor of the column, unique among the data type descriptors pertaining to the table. This is mainly useful for joining with other instances of such identifiers. (The specific format of the identifier is not defined and not guaranteed to remain the same in future versions.) </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> <code class="structfield">is_derived_reference_attribute</code> <code class="type">yes_or_no</code> </p> <p> Applies to a feature not available in <span class="productname">PostgreSQL</span> </p></td></tr></tbody></table></div></div><br class="table-break" /><p> See also under <a class="xref" href="infoschema-columns.html" title="37.17. columns">Section 37.17</a>, a similarly structured view, for further information on some of the columns. </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="infoschema-applicable-roles.html" title="37.5. applicable_roles">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="information-schema.html" title="Chapter 37. The Information Schema">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="infoschema-character-sets.html" title="37.7. character_sets">Next</a></td></tr><tr><td width="40%" align="left" valign="top">37.5. <code class="literal">applicable_roles</code> </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 37.7. <code class="literal">character_sets</code></td></tr></table></div></body></html>