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Comment:Add section to lang_expr.html for the EXISTS operator.
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SHA1: c8e9d99b1dfd190cc398aea4bb5d9ed028fb4b5c
User & Date: dan 2010-09-02 11:52:29
Context
2010-09-02
19:21
Reword some testable statements related to scalar subqueries in lang_expr.html. check-in: 573431382a user: dan tags: trunk
11:52
Add section to lang_expr.html for the EXISTS operator. check-in: c8e9d99b1d user: dan tags: trunk
04:20
More typo fixes. check-in: db66d3a1d4 user: shaneh tags: trunk
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Changes to pages/lang.in.

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</center>)^

<p>^Note that SQLite allows the parenthesized list of scalar values on
the right-hand side of an IN or NOT IN operator to be an empty list but
most other SQL database database engines and the SQL92 standard require
the list to contain at least one element.</p>















<h3>Table Column Names</h3>
<p>^A column name can be any of the names defined in the [CREATE TABLE]
statement or one of the following special identifiers: "<b>ROWID</b>",
"<b>OID</b>", or "<b>_ROWID_</b>".
^These special identifiers all describe the
unique integer key (the [rowid]) associated with every 







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</center>)^

<p>^Note that SQLite allows the parenthesized list of scalar values on
the right-hand side of an IN or NOT IN operator to be an empty list but
most other SQL database database engines and the SQL92 standard require
the list to contain at least one element.</p>

<tcl>hd_fragment in_op {EXISTS operator} {NOT EXISTS operator}</tcl>
<h3>The EXISTS operator</h3>

<p>^The EXISTS operator always evaluates to one of the integer values 0 
and 1. ^If executing the SELECT statement specified as the right-hand 
operand of the EXISTS operator would return one or more rows, then the
EXISTS operator evaluates to 1. ^If executing the SELECT would return
no rows at all, then the EXISTS operator evaluates to 0. 

<p>^The number of columns in each row returned by the SELECT statement
(if any) and the specific values returned have no effect on the results
of the EXISTS operator. ^In particular, rows containing NULL values are
not handled any differently from rows without NULL values.

<h3>Table Column Names</h3>
<p>^A column name can be any of the names defined in the [CREATE TABLE]
statement or one of the following special identifiers: "<b>ROWID</b>",
"<b>OID</b>", or "<b>_ROWID_</b>".
^These special identifiers all describe the
unique integer key (the [rowid]) associated with every