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<span style="font-family:Helvetica,Arial; font-size:12pt; color:#000000"><b>Logical Operators
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Absolute Database supports usual logical operators:
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><b><u>Operator</u></b>
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><b><u>Description</u></b>
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><b><u>Example</u></b>
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">AND
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">Both conditions must apply
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">(ID &gt; 1) AND (ID &lt; 100)
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">OR
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">Either condition can apply
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">(Color = 'Blue') OR (Color = 'Red')
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">NOT
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">Logical opposite of condition
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<span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">NOT (State = 'CA')
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SQL uses a three-valued Boolean logic where the null value represents "unknown". 
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Observe the following truth tables: <span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000"><b>a</b>
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000"><b>b</b>
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000"><b>a AND b</b>
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000"><b>a OR b</b>
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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</span></td></tr><tr><td align="left" valign="top" width="63">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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</span></td><td align="left" valign="top" width="76">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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</span></td><td align="left" valign="top" width="72">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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</span></td></tr><tr><td align="left" valign="top" width="63">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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</span></td><td align="left" valign="top" width="76">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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</span></td><td align="left" valign="top" width="71">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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<b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
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<table border="0" cellpadding="1"><tr><td align="left" valign="top" width="65">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000"><b>a</b>
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000"><b>NOT a</b>
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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</span></td></tr><tr><td align="left" valign="top" width="65">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">FALSE
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</span></td><td align="left" valign="top" width="72">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">TRUE
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</span></td></tr><tr><td align="left" valign="top" width="65">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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</span></td><td align="left" valign="top" width="72">
<span style="font-family:Times New Roman; font-size:12pt; color:#000000">NULL
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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
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</b></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">The operators AND and OR are commutative, that is, you can switch the left and right operand without affecting the result. </span><span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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