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<chapter id="queries">

<title>Queries</title>

<varlistentry>

<term>CROSS JOIN</term>

<indexterm>

<primary>joins</primary>

<secondary>cross</secondary>

</indexterm>

<listitem>

<indexterm>

<primary>joins</primary>

<secondary>cross</secondary>

</indexterm>

<synopsis>

<replaceable>T1</replaceable> CROSS JOIN <replaceable>T2</replaceable>

</synopsis>

<varlistentry>

<term>Qualified joins</term>

<listitem>

<indexterm>

<primary>joins</primary>

<secondary>outer</secondary>

</indexterm>

<indexterm>

<primary>joins</primary>

<secondary>outer</secondary>

</indexterm>

<listitem>

<synopsis>

<replaceable>T1</replaceable> { <optional>INNER</optional> | { LEFT | RIGHT | FULL } <optional>OUTER</optional> } JOIN <replaceable>T2</replaceable> ON <replaceable>boolean_expression</replaceable>

<replaceable>T1</replaceable> { <optional>INNER</optional> | { LEFT | RIGHT | FULL } <optional>OUTER</optional> } JOIN <replaceable>T2</replaceable> USING ( <replaceable>join column list</replaceable> )

<varlistentry>

<term>LEFT OUTER JOIN</term>

<listitem>

<indexterm>

<primary>joins</primary>

<secondary>left</secondary>

</indexterm>

<indexterm>

<primary>joins</primary>

<secondary>left</secondary>

</indexterm>

<listitem>

<para>

First, an INNER JOIN is performed. Then, for each row in T1

that does not satisfy the join condition with any row in