Difference between revisions of "NULL Predicate"

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==See Also==
 
==See Also==
[[SQL Predicates|PREDICATES]], [[SQL INSERT|INSERT]], [[SQL SELECT|SELECT]], [[SQL UPDATE|UPDATE]]
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[[SQL INSERT|INSERT]], [[SQL Predicates|PREDICATES]], [[SQL SELECT|SELECT]], [[SQL UPDATE|UPDATE]]
  
  
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==Example==
 
==Example==
 
<code lang="recital">
 
<code lang="recital">
 
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SELECT name, address, balance, cost*1.15;
EXEC SQL
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  FROM accounts;
SELECT name, address, balance, cost*1.15
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  WHERE paid_date < date() AND ord_value IS NULL;
FROM accounts
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  ORDER BY name, paid_date
WHERE paid_date < date() AND ord_value IS NULL
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ORDER BY name, paid_date;
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</code>
 
</code>
  
  
 
==Products==
 
==Products==
Recital Database Server, Recital Mirage Server, Recital Terminal Developer
+
Recital, Recital Server
 
[[Category:Documentation]]
 
[[Category:Documentation]]
 
[[Category:SQL]]
 
[[Category:SQL]]

Latest revision as of 17:21, 22 December 2009

Purpose

Special predicate


Syntax

<expression> IS [NOT] NULL


See Also

INSERT, PREDICATES, SELECT, UPDATE


Description

NULL is a special predicate to evaluate whether the specified <expression> is NULL. The optional NOT can be used to evaluate whether the specified <expression> is not NULL.


Example

SELECT name, address, balance, cost*1.15;
  FROM accounts;
  WHERE paid_date < date() AND ord_value IS NULL;
  ORDER BY name, paid_date


Products

Recital, Recital Server