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doc-exports/docs/dws/dev/dws_06_0341.html
Lu, Huayi ef0ada5a59 DWS DEV 20240716 version 
Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com>
Co-authored-by: Lu, Huayi <luhuayi@huawei.com>
Co-committed-by: Lu, Huayi <luhuayi@huawei.com>
2024-11-02 09:07:47 +00:00

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<a name="EN-US_TOPIC_0000001460561440"></a><a name="EN-US_TOPIC_0000001460561440"></a>
<h1 class="topictitle1">System Catalog Information Functions</h1>
<div id="body0000001503323525"><div class="section" id="EN-US_TOPIC_0000001460561440__section20363125015301"><h4 class="sectiontitle">format_type(type_oid, typemod)</h4><p id="EN-US_TOPIC_0000001460561440__p1936211508302">Description: Gets SQL name of a data type.</p>
<p id="EN-US_TOPIC_0000001460561440__p1736225033012">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p1536215019302">Note:</p>
<p id="EN-US_TOPIC_0000001460561440__p33621450173010"><strong id="EN-US_TOPIC_0000001460561440__b207737349317">format_type</strong> returns the SQL name of a data type that is identified by its type OID and possibly a type modifier. Pass NULL for the type modifier if no specific modifier is known. Certain type modifiers are passed for data types with length limitations. The SQL name returned from <strong id="EN-US_TOPIC_0000001460561440__b1493913656101736">format_type</strong> contains the length of the data type, which can be calculated by taking sizeof(int32) from actual storage length [actual storage len - sizeof(int32)] in the unit of bytes. 32-bit space is required to store the customized length set by users. So the actual storage length contains 4 bytes more than the customized length. In the following example, the SQL name returned from <strong id="EN-US_TOPIC_0000001460561440__b1768696702101736">format_type</strong> is character varying(6), indicating the length of varchar type is 6 bytes. So the actual storage length of varchar type is 10 bytes.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen1736335020305"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span>
<span class="normal">3</span>
<span class="normal">4</span>
<span class="normal">5</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="n">format_type</span><span class="p">((</span><span class="k">SELECT</span><span class="w"> </span><span class="n">oid</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_type</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">typname</span><span class="o">=</span><span class="s1">'varchar'</span><span class="p">),</span><span class="w"> </span><span class="mi">10</span><span class="p">);</span>
<span class="w"> </span><span class="n">format_type</span><span class="w"> </span>
<span class="c1">----------------------</span>
<span class="w"> </span><span class="nb">character</span><span class="w"> </span><span class="nb">varying</span><span class="p">(</span><span class="mi">6</span><span class="p">)</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section12935246183015"><h4 class="sectiontitle">pg_check_authid(role_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p149351546103016">Description: Check whether a role name with given OID exists.</p>
<p id="EN-US_TOPIC_0000001460561440__p19935134653018">Return type: Boolean</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section171321844143014"><h4 class="sectiontitle">pg_describe_object(catalog_id, object_id, object_sub_id)</h4><p id="EN-US_TOPIC_0000001460561440__p2131164473015">Description: Gets description of a database object.</p>
<p id="EN-US_TOPIC_0000001460561440__p18131134473010">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p15131344183017">Note: <strong id="EN-US_TOPIC_0000001460561440__b1712671453101736">pg_describe_object</strong> returns a description of a database object specified by catalog OID, object OID and a (possibly zero) sub-object ID. This is useful to determine the identity of an object as stored in the <strong id="EN-US_TOPIC_0000001460561440__b474824248101736">pg_depend</strong> catalog.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section14944941193012"><h4 class="sectiontitle">pg_get_constraintdef(constraint_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p119441541113018">Description: Gets definition of a constraint.</p>
<p id="EN-US_TOPIC_0000001460561440__p199441541143011">Return type: text</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section116711238143019"><h4 class="sectiontitle">pg_get_constraintdef(constraint_oid, pretty_bool)</h4><p id="EN-US_TOPIC_0000001460561440__p1967010382309">Description: Gets definition of a constraint.</p>
<p id="EN-US_TOPIC_0000001460561440__p9671163833015">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p1467112387309">Note: <strong id="EN-US_TOPIC_0000001460561440__b1435928942101736">pg_get_constraintdef</strong> and <strong id="EN-US_TOPIC_0000001460561440__b2091381889101736">pg_get_indexdef</strong> respectively reconstruct the creating command for a constraint and an index. </p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section526173653011"><h4 class="sectiontitle">pg_get_expr(pg_node_tree, relation_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p1326173683015">Description: Decompiles internal form of an expression, assuming that any Vars in it refer to the relationship indicated by the second parameter.</p>
<p id="EN-US_TOPIC_0000001460561440__p15261936113014">Return type: text</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section4728103210304"><h4 class="sectiontitle">pg_get_expr(pg_node_tree, relation_oid, pretty_bool)</h4><p id="EN-US_TOPIC_0000001460561440__p13728183293012">Description: Decompiles internal form of an expression, assuming that any Vars in it refer to the relationship indicated by the second parameter.</p>
<p id="EN-US_TOPIC_0000001460561440__p1872813213309">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p2728133283019">Note: <strong id="EN-US_TOPIC_0000001460561440__b465093327101736">pg_get_expr</strong> decompiles the internal form of an individual expression, such as the default value for a column. It can be useful when examining the contents of system catalogs. If the expression might contain Vars, specify the OID of the relationship they refer to as the second parameter; if no Vars are expected, zero is sufficient.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section433772983011"><h4 class="sectiontitle">pg_get_functiondef(func_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p1233642963020">Description: Gets definition of a function.</p>
<p id="EN-US_TOPIC_0000001460561440__p23367298300">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p193362029183016"><strong id="EN-US_TOPIC_0000001460561440__b791290782101736">func_oid</strong> is the OID of the function, which can be queried in the <strong id="EN-US_TOPIC_0000001460561440__b1365503342101736">PG_PROC</strong> system catalog.</p>
<p id="EN-US_TOPIC_0000001460561440__p17336152913019">Example: Query the OID and definition of the <strong id="EN-US_TOPIC_0000001460561440__b1033623816101736">justify_days</strong> function.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen20337152923010"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal"> 1</span>
<span class="normal"> 2</span>
<span class="normal"> 3</span>
<span class="normal"> 4</span>
<span class="normal"> 5</span>
<span class="normal"> 6</span>
<span class="normal"> 7</span>
<span class="normal"> 8</span>
<span class="normal"> 9</span>
<span class="normal">10</span>
<span class="normal">11</span>
<span class="normal">12</span>
<span class="normal">13</span>
<span class="normal">14</span>
<span class="normal">15</span>
<span class="normal">16</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="n">oid</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_proc</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">proname</span><span class="w"> </span><span class="o">=</span><span class="s1">'justify_days'</span><span class="p">;</span>
<span class="w"> </span><span class="n">oid</span>
<span class="c1">------</span>
<span class="w"> </span><span class="mi">1295</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
<span class="k">SELECT</span><span class="w"> </span><span class="o">*</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_get_functiondef</span><span class="p">(</span><span class="mi">1295</span><span class="p">);</span>
<span class="w"> </span><span class="n">headerlines</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="n">definition</span>
<span class="c1">-------------+--------------------------------------------------------------</span>
<span class="w"> </span><span class="mi">4</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="k">CREATE</span><span class="w"> </span><span class="k">OR</span><span class="w"> </span><span class="k">REPLACE</span><span class="w"> </span><span class="k">FUNCTION</span><span class="w"> </span><span class="n">pg_catalog</span><span class="p">.</span><span class="n">justify_days</span><span class="p">(</span><span class="nb">interval</span><span class="p">)</span><span class="o">+</span>
<span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="k">RETURNS</span><span class="w"> </span><span class="nb">interval</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="k">LANGUAGE</span><span class="w"> </span><span class="n">internal</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="k">IMMUTABLE</span><span class="w"> </span><span class="k">STRICT</span><span class="w"> </span><span class="k">NOT</span><span class="w"> </span><span class="n">FENCED</span><span class="w"> </span><span class="k">NOT</span><span class="w"> </span><span class="n">SHIPPABLE</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="k">AS</span><span class="w"> </span><span class="err">$</span><span class="k">function</span><span class="err">$</span><span class="n">interval_justify_days$function$</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="o">|</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
<p id="EN-US_TOPIC_0000001460561440__p1135516321532">Note: The query result returned by <strong id="EN-US_TOPIC_0000001460561440__b628413397241">pg_get_functiondef</strong> is in the original text format of the stored procedure. The escape character (\) is used to facilitate subsequent parsing.</p>
<div class="section" id="EN-US_TOPIC_0000001460561440__section152821625113017"><h4 class="sectiontitle">pg_get_function_arguments(func_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p16282025203019">Description: Gets argument list of function's definition (with default values).</p>
<p id="EN-US_TOPIC_0000001460561440__p228272513305">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p328216257308">Note: <strong id="EN-US_TOPIC_0000001460561440__b1746898827101736">pg_get_function_arguments</strong> returns the argument list of a function, in the form it would need to appear in within <strong id="EN-US_TOPIC_0000001460561440__b518787535101736">CREATE FUNCTION</strong>.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section18986921103019"><h4 class="sectiontitle">pg_get_function_identity_arguments(func_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p798642114305">Description: Gets argument list to identify a function (without default values).</p>
<p id="EN-US_TOPIC_0000001460561440__p1986152103012">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p1398642110302">Note: <strong id="EN-US_TOPIC_0000001460561440__b1038701779101736">pg_get_function_identity_arguments</strong> returns the argument list necessary to identify a function, in the form it would need to appear in within <strong id="EN-US_TOPIC_0000001460561440__b1252307982101736">ALTER FUNCTION</strong>. This form omits default values.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section71211451152916"><h4 class="sectiontitle">pg_get_function_result(func_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p1112195162913">Description: Gets <strong id="EN-US_TOPIC_0000001460561440__b913565709101736">RETURNS</strong> clause for function.</p>
<p id="EN-US_TOPIC_0000001460561440__p19121751172912">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p18121851182915">Note: <strong id="EN-US_TOPIC_0000001460561440__b544307891101736">pg_get_function_result</strong> returns the appropriate <strong id="EN-US_TOPIC_0000001460561440__b1764257967101736">RETURNS</strong> clause for the function.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section1358684717297"><h4 class="sectiontitle">pg_get_indexdef(index_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p05857473297">Description: Gets <strong id="EN-US_TOPIC_0000001460561440__b1486496634101736">CREATE INDEX</strong> command for index.</p>
<p id="EN-US_TOPIC_0000001460561440__p9585164711294">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p18585104715291"><strong id="EN-US_TOPIC_0000001460561440__b1794880425101736">index_oid</strong> indicates the index OID, which can be queried in the <strong id="EN-US_TOPIC_0000001460561440__b924925160101736">PG_STATIO_ALL_INDEXES</strong> system view.</p>
<p id="EN-US_TOPIC_0000001460561440__p55851647142914">Example: Query the OID and CREATE INDEX command of <strong id="EN-US_TOPIC_0000001460561440__b1394253244101736">index ds_ship_mode_t1_index1</strong>.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen16586134752916"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal"> 1</span>
<span class="normal"> 2</span>
<span class="normal"> 3</span>
<span class="normal"> 4</span>
<span class="normal"> 5</span>
<span class="normal"> 6</span>
<span class="normal"> 7</span>
<span class="normal"> 8</span>
<span class="normal"> 9</span>
<span class="normal">10</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="n">indexrelid</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">PG_STATIO_ALL_INDEXES</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">indexrelname</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="s1">'ds_ship_mode_t1_index1'</span><span class="p">;</span>
<span class="w"> </span><span class="n">indexrelid</span>
<span class="c1">------------</span>
<span class="w"> </span><span class="mi">136035</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
<span class="k">SELECT</span><span class="w"> </span><span class="o">*</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_get_indexdef</span><span class="p">(</span><span class="mi">136035</span><span class="p">);</span>
<span class="w"> </span><span class="n">pg_get_indexdef</span>
<span class="c1">---------------------------------------------------------------------------------------------------------------</span>
<span class="w"> </span><span class="k">CREATE</span><span class="w"> </span><span class="k">INDEX</span><span class="w"> </span><span class="n">ds_ship_mode_t1_index1</span><span class="w"> </span><span class="k">ON</span><span class="w"> </span><span class="n">tpcds</span><span class="p">.</span><span class="n">ship_mode_t1</span><span class="w"> </span><span class="k">USING</span><span class="w"> </span><span class="n">psort</span><span class="w"> </span><span class="p">(</span><span class="n">sm_ship_mode_sk</span><span class="p">)</span><span class="w"> </span><span class="n">TABLESPACE</span><span class="w"> </span><span class="n">pg_default</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section16112422298"><h4 class="sectiontitle">pg_get_indexdef(index_oid, column_no, pretty_bool)</h4><p id="EN-US_TOPIC_0000001460561440__p18101642142911">Description: Gets <strong id="EN-US_TOPIC_0000001460561440__b187807321101736">CREATE INDEX</strong> command for index, or definition of just one index column when <strong id="EN-US_TOPIC_0000001460561440__b1891227131101736">column_no</strong> is not zero.</p>
<p id="EN-US_TOPIC_0000001460561440__p16101842192910">Return type: text</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen111104215294"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal"> 1</span>
<span class="normal"> 2</span>
<span class="normal"> 3</span>
<span class="normal"> 4</span>
<span class="normal"> 5</span>
<span class="normal"> 6</span>
<span class="normal"> 7</span>
<span class="normal"> 8</span>
<span class="normal"> 9</span>
<span class="normal">10</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="o">*</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_get_indexdef</span><span class="p">(</span><span class="mi">136035</span><span class="p">,</span><span class="mi">0</span><span class="p">,</span><span class="k">false</span><span class="p">);</span>
<span class="w"> </span><span class="n">pg_get_indexdef</span>
<span class="c1">---------------------------------------------------------------------------------------------------------------</span>
<span class="w"> </span><span class="k">CREATE</span><span class="w"> </span><span class="k">INDEX</span><span class="w"> </span><span class="n">ds_ship_mode_t1_index1</span><span class="w"> </span><span class="k">ON</span><span class="w"> </span><span class="n">tpcds</span><span class="p">.</span><span class="n">ship_mode_t1</span><span class="w"> </span><span class="k">USING</span><span class="w"> </span><span class="n">psort</span><span class="w"> </span><span class="p">(</span><span class="n">sm_ship_mode_sk</span><span class="p">)</span><span class="w"> </span><span class="n">TABLESPACE</span><span class="w"> </span><span class="n">pg_default</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
<span class="k">SELECT</span><span class="w"> </span><span class="o">*</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_get_indexdef</span><span class="p">(</span><span class="mi">136035</span><span class="p">,</span><span class="mi">1</span><span class="p">,</span><span class="k">false</span><span class="p">);</span>
<span class="w"> </span><span class="n">pg_get_indexdef</span>
<span class="c1">-----------------</span>
<span class="w"> </span><span class="n">sm_ship_mode_sk</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section1762333312291"><h4 class="sectiontitle">pg_get_keywords()</h4><p id="EN-US_TOPIC_0000001460561440__p1062333312918">Description: Gets list of SQL keywords and their categories.</p>
<p id="EN-US_TOPIC_0000001460561440__p162313311299">Return type: SETOF record</p>
<p id="EN-US_TOPIC_0000001460561440__p1962320338297">Note: <strong id="EN-US_TOPIC_0000001460561440__b1023108523101736">pg_get_keywords</strong> returns a set of records describing the SQL keywords recognized by the server. The <strong id="EN-US_TOPIC_0000001460561440__b657274614101736">word</strong> column contains the keyword. The <strong id="EN-US_TOPIC_0000001460561440__b1520279868101736">catcode</strong> column contains a category code: <strong id="EN-US_TOPIC_0000001460561440__b1547773149101736">U</strong> for unreserved, <strong id="EN-US_TOPIC_0000001460561440__b1195387910101736">C</strong> for column name, <strong id="EN-US_TOPIC_0000001460561440__b924479643101736">T</strong> for type or function name, or <strong id="EN-US_TOPIC_0000001460561440__b3781381101736">R</strong> for reserved. The <strong id="EN-US_TOPIC_0000001460561440__b139682925101736">catdesc</strong> column contains a possibly-localized string describing the category.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section12255103110299"><h4 class="sectiontitle">pg_get_ruledef(rule_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p192558312297">Description: Gets <strong id="EN-US_TOPIC_0000001460561440__b1934002572101736">CREATE RULE</strong> command for a rule.</p>
<p id="EN-US_TOPIC_0000001460561440__p102551631132917">Return type: text</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section1444032872911"><h4 class="sectiontitle">pg_get_ruledef(rule_oid, pretty_bool)</h4><p id="EN-US_TOPIC_0000001460561440__p17440928152915">Description: Gets <strong id="EN-US_TOPIC_0000001460561440__b1823865466101736">CREATE RULE</strong> command for a rule.</p>
<p id="EN-US_TOPIC_0000001460561440__p164400287297">Return type: text</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section195363253295"><h4 class="sectiontitle">pg_get_userbyid(role_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p1753672582917">Description: Gets role name with given OID.</p>
<p id="EN-US_TOPIC_0000001460561440__p45364253296">Return type: name</p>
<p id="EN-US_TOPIC_0000001460561440__p17536525192913">Note: <strong id="EN-US_TOPIC_0000001460561440__b1056604154101736">pg_get_userbyid</strong> extracts a role's name given its OID.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section1335252211294"><h4 class="sectiontitle">pg_get_viewdef(viewname text [, pretty bool [, fullflag bool]])</h4><p id="EN-US_TOPIC_0000001460561440__p2351172202917">Description: gets underlying <strong id="EN-US_TOPIC_0000001460561440__b5965777101736">SELECT</strong> command for views.</p>
<p id="EN-US_TOPIC_0000001460561440__p1135117229299">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p123511222192914">Note:</p>
<ul id="EN-US_TOPIC_0000001460561440__ul6351522172915"><li id="EN-US_TOPIC_0000001460561440__li11351822182917"><strong id="EN-US_TOPIC_0000001460561440__b1502028130101736">pg_get_viewdef</strong> reconstructs the <strong id="EN-US_TOPIC_0000001460561440__b1576319765101736">SELECT</strong> query that defines a view. If the value of <strong id="EN-US_TOPIC_0000001460561440__b1606441524101736">pretty bool</strong> is set to <strong id="EN-US_TOPIC_0000001460561440__b1153650093101736">true</strong>, the display format is suitable for printing and more readable. The default value of <strong id="EN-US_TOPIC_0000001460561440__b933796775101736">pretty bool</strong> is <strong id="EN-US_TOPIC_0000001460561440__b366464817101736">false</strong>, and the display format is not readable. Use the default format for dump purposes whenever possible. The <strong id="EN-US_TOPIC_0000001460561440__b1916515886101736">pretty bool</strong> parameter can be applied only to valid views.</li><li id="EN-US_TOPIC_0000001460561440__li14351622132920">When <strong id="EN-US_TOPIC_0000001460561440__b1581490497101736">fullflag bool</strong> is set to <strong id="EN-US_TOPIC_0000001460561440__b1424186371101736">true</strong>, the complete definition of the view is displayed. The default value is <strong id="EN-US_TOPIC_0000001460561440__b863808697101736">false</strong>.</li></ul>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section16470161915298"><h4 class="sectiontitle">pg_get_viewdef(viewoid oid [, pretty bool [, fullflag bool]])</h4><p id="EN-US_TOPIC_0000001460561440__p1447041917291">Description: gets underlying <strong id="EN-US_TOPIC_0000001460561440__b663670536101736">SELECT</strong> command for views.</p>
<p id="EN-US_TOPIC_0000001460561440__p12470519192911">Return type: text</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section1034181762914"><h4 class="sectiontitle">pg_get_viewdef(view_oid, wrap_column_int)</h4><p id="EN-US_TOPIC_0000001460561440__p13441711297">Description: Gets underlying SELECT command for view, wrapping lines with columns as specified, printing is implied.</p>
<p id="EN-US_TOPIC_0000001460561440__p143416179292">Return type: text</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section1537951362911"><h4 class="sectiontitle">pg_get_tabledef(table_oid)</h4><p id="EN-US_TOPIC_0000001460561440__p23778134296">Description: Obtains a table definition based on <strong id="EN-US_TOPIC_0000001460561440__b147538964101736">table_oid</strong>.</p>
<p id="EN-US_TOPIC_0000001460561440__p123771313122916">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p14378913152912">Example: Obtain the OID of the table <strong id="EN-US_TOPIC_0000001460561440__b628414923101736">customer_t2</strong> from the system catalog <strong id="EN-US_TOPIC_0000001460561440__b865315953101736">pg_class</strong>, and then use this function to query the definition of <strong id="EN-US_TOPIC_0000001460561440__b911037565101736">customer_t2</strong> to obtain the table columns, storage mode (row-store or column-store), and table distribution mode configured for <strong id="EN-US_TOPIC_0000001460561440__b1186470310101736">customer_t2</strong> when it is created.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen737910133295"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal"> 1</span>
<span class="normal"> 2</span>
<span class="normal"> 3</span>
<span class="normal"> 4</span>
<span class="normal"> 5</span>
<span class="normal"> 6</span>
<span class="normal"> 7</span>
<span class="normal"> 8</span>
<span class="normal"> 9</span>
<span class="normal">10</span>
<span class="normal">11</span>
<span class="normal">12</span>
<span class="normal">13</span>
<span class="normal">14</span>
<span class="normal">15</span>
<span class="normal">16</span>
<span class="normal">17</span>
<span class="normal">18</span>
<span class="normal">19</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">select</span><span class="w"> </span><span class="n">oid</span><span class="w"> </span><span class="k">from</span><span class="w"> </span><span class="n">pg_class</span><span class="w"> </span><span class="k">where</span><span class="w"> </span><span class="n">relname</span><span class="w"> </span><span class="o">=</span><span class="s1">'customer_t2'</span><span class="p">;</span>
<span class="w"> </span><span class="n">oid</span>
<span class="c1">-------</span>
<span class="w"> </span><span class="mi">17353</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
<span class="k">select</span><span class="w"> </span><span class="o">*</span><span class="w"> </span><span class="k">from</span><span class="w"> </span><span class="n">pg_get_tabledef</span><span class="p">(</span><span class="mi">17353</span><span class="p">);</span>
<span class="w"> </span><span class="n">pg_get_tabledef</span>
<span class="c1">--------------------------------------------</span>
<span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">search_path</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">dbadmin</span><span class="p">;</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="k">CREATE</span><span class="w"> </span><span class="k">TABLE</span><span class="w"> </span><span class="n">customer_t2</span><span class="w"> </span><span class="p">(</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="n">state_id</span><span class="w"> </span><span class="nb">character</span><span class="p">(</span><span class="mi">2</span><span class="p">),</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="n">state_name</span><span class="w"> </span><span class="nb">character</span><span class="w"> </span><span class="nb">varying</span><span class="p">(</span><span class="mi">40</span><span class="p">),</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="n">area_id</span><span class="w"> </span><span class="nb">numeric</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="p">)</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="k">WITH</span><span class="w"> </span><span class="p">(</span><span class="n">orientation</span><span class="o">=</span><span class="k">column</span><span class="p">,</span><span class="w"> </span><span class="n">compression</span><span class="o">=</span><span class="n">low</span><span class="p">)</span><span class="o">+</span>
<span class="w"> </span><span class="n">DISTRIBUTE</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="n">HASH</span><span class="p">(</span><span class="n">state_id</span><span class="p">)</span><span class="w"> </span><span class="o">+</span>
<span class="w"> </span><span class="k">TO</span><span class="w"> </span><span class="k">GROUP</span><span class="w"> </span><span class="n">group_version1</span><span class="p">;</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section16946188112911"><h4 class="sectiontitle">pg_get_tabledef(table_name)</h4><p id="EN-US_TOPIC_0000001460561440__p59469812915">Description: Obtains a table definition based on <strong id="EN-US_TOPIC_0000001460561440__b1121653012101736">table_name</strong>.</p>
<p id="EN-US_TOPIC_0000001460561440__p5946128122919">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p17946158132914">Remarks: <strong id="EN-US_TOPIC_0000001460561440__b1043754993101736">pg_get_tabledef</strong> reconstructs the <strong id="EN-US_TOPIC_0000001460561440__b1474351570101736">CREATE</strong> statement of the table definition, including the table definition, index information, and comments. Users need to create the dependent objects of the table, such as groups, schemas, tablespaces, and servers. The table definition does not include the statements for creating these dependent objects.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section0745115152913"><h4 class="sectiontitle">pg_options_to_table(reloptions)</h4><p id="EN-US_TOPIC_0000001460561440__p37442057299">Description: Gets the set of storage option name/value pairs.</p>
<p id="EN-US_TOPIC_0000001460561440__p57452050294">Return type: SETOF record</p>
<p id="EN-US_TOPIC_0000001460561440__p974518517290">Note: <strong id="EN-US_TOPIC_0000001460561440__b2124102870101736">pg_options_to_table</strong> returns the set of storage option name/value pairs (<strong id="EN-US_TOPIC_0000001460561440__b1098869960101736">option_name</strong>/<strong id="EN-US_TOPIC_0000001460561440__b1622667920101736">option_value</strong>) when passing <strong id="EN-US_TOPIC_0000001460561440__b898860671101736">pg_class.reloptions</strong> or <strong id="EN-US_TOPIC_0000001460561440__b306803095101736">pg_attribute.attoptions</strong>.</p>
<p id="EN-US_TOPIC_0000001460561440__p1235135819436">Example:</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen42461531185210"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span>
<span class="normal">3</span>
<span class="normal">4</span>
<span class="normal">5</span>
<span class="normal">6</span>
<span class="normal">7</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">CREATE</span><span class="w"> </span><span class="k">TABLE</span><span class="w"> </span><span class="n">customer_test</span>
<span class="p">(</span>
<span class="w"> </span><span class="n">state_ID</span><span class="w"> </span><span class="nb">CHAR</span><span class="p">(</span><span class="mi">2</span><span class="p">),</span>
<span class="w"> </span><span class="n">state_NAME</span><span class="w"> </span><span class="n">VARCHAR2</span><span class="p">(</span><span class="mi">40</span><span class="p">),</span>
<span class="w"> </span><span class="n">area_ID</span><span class="w"> </span><span class="nb">NUMBER</span>
<span class="p">)</span>
<span class="k">WITH</span><span class="w"> </span><span class="p">(</span><span class="n">ORIENTATION</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">COLUMN</span><span class="p">,</span><span class="n">COMPRESSION</span><span class="o">=</span><span class="n">middle</span><span class="p">);</span>
</pre></div></td></tr></table></div>
</div>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen122559361328"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span>
<span class="normal">3</span>
<span class="normal">4</span>
<span class="normal">5</span>
<span class="normal">6</span>
<span class="normal">7</span>
<span class="normal">8</span>
<span class="normal">9</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="n">pg_options_to_table</span><span class="p">(</span><span class="n">reloptions</span><span class="p">)</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_class</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">relname</span><span class="o">=</span><span class="s1">'customer_test'</span><span class="p">;</span>
<span class="n">pg_options_to_table</span>
<span class="c1">----------------------</span>
<span class="w"> </span><span class="p">(</span><span class="n">orientation</span><span class="p">,</span><span class="k">column</span><span class="p">)</span>
<span class="w"> </span><span class="p">(</span><span class="n">compression</span><span class="p">,</span><span class="n">middle</span><span class="p">)</span>
<span class="w"> </span><span class="p">(</span><span class="n">bucketnums</span><span class="p">,</span><span class="mi">16384</span><span class="p">)</span>
<span class="w"> </span><span class="p">(</span><span class="n">colversion</span><span class="p">,</span><span class="mi">2</span><span class="p">.</span><span class="mi">0</span><span class="p">)</span>
<span class="w"> </span><span class="p">(</span><span class="n">enable_delta</span><span class="p">,</span><span class="k">false</span><span class="p">)</span>
<span class="p">(</span><span class="mi">5</span><span class="w"> </span><span class="k">rows</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section10267754102814"><h4 class="sectiontitle">pg_typeof(any)</h4><p id="EN-US_TOPIC_0000001460561440__p22661546281">Description: Gets the data type of any value.</p>
<p id="EN-US_TOPIC_0000001460561440__p1026614546283">Return type: regtype</p>
<p id="EN-US_TOPIC_0000001460561440__p7266454192816">Note:</p>
<p id="EN-US_TOPIC_0000001460561440__p1126617542282"><strong id="EN-US_TOPIC_0000001460561440__b1936649166101736">pg_typeof</strong> returns the OID of the data type of the value that is passed to it. This can be helpful for troubleshooting or dynamically constructing SQL queries. The function is declared as returning <strong id="EN-US_TOPIC_0000001460561440__b16279208101736">regtype</strong>, which is an OID alias type (see <a href="dws_06_0022.html">Object Identifier Types</a>). This means that it is the same as an OID for comparison purposes but displays as a type name.</p>
<p id="EN-US_TOPIC_0000001460561440__p11267145416289">Example:</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen4267145432812"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal"> 1</span>
<span class="normal"> 2</span>
<span class="normal"> 3</span>
<span class="normal"> 4</span>
<span class="normal"> 5</span>
<span class="normal"> 6</span>
<span class="normal"> 7</span>
<span class="normal"> 8</span>
<span class="normal"> 9</span>
<span class="normal">10</span>
<span class="normal">11</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="n">pg_typeof</span><span class="p">(</span><span class="mi">33</span><span class="p">);</span>
<span class="w"> </span><span class="n">pg_typeof</span><span class="w"> </span>
<span class="c1">-----------</span>
<span class="w"> </span><span class="nb">integer</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
<span class="k">SELECT</span><span class="w"> </span><span class="n">typlen</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_type</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">oid</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">pg_typeof</span><span class="p">(</span><span class="mi">33</span><span class="p">);</span>
<span class="w"> </span><span class="n">typlen</span><span class="w"> </span>
<span class="c1">--------</span>
<span class="w"> </span><span class="mi">4</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section88274493281"><h4 class="sectiontitle">collation for (any)</h4><p id="EN-US_TOPIC_0000001460561440__p17827114917289">Description: Gets the collation of the parameter.</p>
<p id="EN-US_TOPIC_0000001460561440__p782754916286">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p0827144962812">Note:</p>
<p id="EN-US_TOPIC_0000001460561440__p158272491283">The expression <strong id="EN-US_TOPIC_0000001460561440__b1675345670101736">collation for</strong> returns the collation of the value that is passed to it. Example:</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen7827184917281"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span>
<span class="normal">3</span>
<span class="normal">4</span>
<span class="normal">5</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="k">collation</span><span class="w"> </span><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="n">description</span><span class="p">)</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">pg_description</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span>
<span class="w"> </span><span class="n">pg_collation_for</span><span class="w"> </span>
<span class="c1">------------------</span>
<span class="w"> </span><span class="ss">&quot;default&quot;</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001460561440__p1982754912283">The value might be quoted and schema-qualified. If no collation is derived for the argument expression, then a null value is returned. If the parameter is not of a collectable data type, then an error is thrown.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001460561440__section10103025111217"><h4 class="sectiontitle">getdistributekey(table_name)</h4><p id="EN-US_TOPIC_0000001460561440__p101015256121">Description: Gets a distribution column for a hash table.</p>
<p id="EN-US_TOPIC_0000001460561440__p6101825171219">Return type: text</p>
<p id="EN-US_TOPIC_0000001460561440__p3101325191214">Example:</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001460561440__screen41031925161215"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span>
<span class="normal">3</span>
<span class="normal">4</span>
<span class="normal">5</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="n">getdistributekey</span><span class="p">(</span><span class="s1">'item'</span><span class="p">);</span>
<span class="w"> </span><span class="n">getdistributekey</span><span class="w"> </span>
<span class="c1">------------------</span>
<span class="w"> </span><span class="n">i_item_sk</span>
<span class="p">(</span><span class="mi">1</span><span class="w"> </span><span class="k">row</span><span class="p">)</span>
</pre></div></td></tr></table></div>
</div>
</div>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dws_06_0051.html">System Information Functions</a></div>
</div>
</div>
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