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<h2 id="collex"><a href="rbafzmst02.htm#ToC_26">Schemas</a></h2><a id="idx26" name="idx26"></a><a id="idx27" name="idx27"></a>
<p>The objects in a relational database are organized into sets called schemas.
A schema provides a logical classification of objects in a relational database.
A <span class="italic">schema name</span> is used as the qualifier of SQL object
names such as tables, views, indees, and triggers. A schema is also called
a collection or library.</p>
<p>Each database manager supports a set of schemas that are reserved for use
by the database manager. Such schemas are called <var class="pv">system schemas</var>. User objects
must not be created in <var class="pv">system schemas</var>, other than SESSION.</p>
<p>The schema SESSION and all schemas that start with 'SYS' and 'Q' are <var class="pv">system schemas</var>. SESSION is always used as the schema name for declared
temporary tables. Users should not create schemas that start with 'SYS' or
'Q'.</p>
<p>A schema is also an object in the relational database. It is explicitly
created using the CREATE SCHEMA statement.<sup class="fn"><a id="wq6" name="wq6" href="rbafzmstcollex.htm#wq7">1</a></sup></p>
<p>An object that is contained in a schema is assigned to the schema when
the object is created. The schema to which it is assigned is determined by
the name of the object if specifically qualified with a schema name or by
the default schema name if not qualified.</p>
<p>For example, a user creates a schema called C:</p>
<pre class="xmp"> <span class="bold">CREATE SCHEMA</span> C </pre>
<p>The user can then issue the following statement to create a table called
X in schema C:</p>
<pre class="xmp"> <span class="bold">CREATE TABLE</span> C.X (COL1 <span class="bold">INT</span>)</pre>
<hr /><div class="fnnum"><a id="wq7" name="wq7" href="rbafzmstcollex.htm#wq6">1</a>.</div>
<div class="fntext">A schema can also be created
using the CRTLIB CL command, however, the catalog views and journal and journal
receiver created by using the CREATE SCHEMA statement will not be created
with CRTLIB.</div>
<br />
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