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Overview
Comment:Update syntax diagrams and expression text to cover the new TRUE and FALSE literals and the IS TRUE and IS FALSE operators.
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SHA3-256: dfdf980e6cb8ba5c0054013379ee8654d4c49f3923a6b8aaed41a2d9f23494d0
User & Date: drh 2018-03-23 14:46:15
Context
2018-03-23
14:53
Clarification of text in the new optoverview.html section on the LEFT JOIN Optimization. check-in: 9e6750c1fc user: drh tags: trunk
14:46
Update syntax diagrams and expression text to cover the new TRUE and FALSE literals and the IS TRUE and IS FALSE operators. check-in: dfdf980e6c user: drh tags: trunk
14:30
Add TRUE and FALSE to the syntax diagrams as new literal values. check-in: 1d1c0fc6ec user: drh tags: trunk
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[CAST expression]. A numeric zero value (integer value 0 or real 
value 0.0) is considered to be false.  A NULL value is still NULL.
All other values are considered true.)^

<p>^(For example, the values NULL, 0.0, 0, 'english' and '0' are all considered
to be false.)^ ^(Values 1, 1.0, 0.1, -0.1 and '1english' are considered to 
be true.)^














<h3>Functions</h3>
<p>SQLite supports many [corefunc|simple] and [aggfunc|aggregate]
SQL functions.  For presentation purposes, simple functions are further
subdivided into [corefunc | core functions] and [datefunc|date-time functions].
Applications can add new functions, written in C/C++, using the
[sqlite3_create_function()] interface.







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[CAST expression]. A numeric zero value (integer value 0 or real 
value 0.0) is considered to be false.  A NULL value is still NULL.
All other values are considered true.)^

<p>^(For example, the values NULL, 0.0, 0, 'english' and '0' are all considered
to be false.)^ ^(Values 1, 1.0, 0.1, -0.1 and '1english' are considered to 
be true.)^

<p>Beginning with SQLite 3.23.0 ([dateof:3.23.0]), SQLite recognizes the
identifiers "TRUE" and "FALSE" as boolean literals, if and only if those
identifiers are not already used for some other meaning.  If there already
exists columns or tables or other objects named TRUE or FALSE, then for
the sake of backwards compatibility, the TRUE and FALSE indentifiers refer
to those other objects, not to the boolean values.

<p>The boolean identifers TRUE and FALSE are usually just aliases for
the integer values 1 and 0, respectively.  However, if TRUE or FALSE
occur on the right-hand side of an IS operator, then they form new
unary postfix operators "IS TRUE" and "IS FALSE" which test the boolean
value of the operand on the left.

<h3>Functions</h3>
<p>SQLite supports many [corefunc|simple] and [aggfunc|aggregate]
SQL functions.  For presentation purposes, simple functions are further
subdivided into [corefunc | core functions] and [datefunc|date-time functions].
Applications can add new functions, written in C/C++, using the
[sqlite3_create_function()] interface.