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handling NULL values in conditions, making it essential to carefully structure queries to account for the "Unknown" state that arises in certain comparisons with NULL values. Proper use of these advanced conditions enhances the flexibility and robustness of SQL queries, particularly in complex data retrieval and reporting environments.
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simplifies the process of handling NULL values by returning the first non-NULL value in a given list of expressions, which is especially useful in scenarios where data might be incomplete or missing. Furthermore, SQL's support for three-valued logic (True, False, Unknown) introduces nuances when
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expression, for example, enables SQL to perform conditional branching within queries, providing a mechanism to return different values based on evaluated conditions. This logic can be particularly useful for data transformation during retrieval, especially in SELECT statements. Meanwhile,
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SQL Routines and Types for the Java
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standard's reserved and non-reserved keywords. EXISTS
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278:has rows of data with a duplicated column
106:Learn how and when to remove this message
721:(2 ed.). Peachpit Press. pp.
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737:SQL Keywords The appendix lists the
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231:one row of data from a table called
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680:Information and Definition Schemas
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336:Advanced Conditional Logic in SQL
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274:To identify whether a table
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753:Fehily, Chris (2005).
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55:"Condition" SQL
40:improve this article
634:Relational database
180:. You can help by
161:Types of condition
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96:December 2009
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38:Please help
33:verification
30:
149:clauses to
131:expressions
702:References
655:Foundation
629:Edgar Codd
127:conditions
66:newspapers
650:Framework
189:July 2010
788:Category
739:SQL:2003
584:Truncate
556:Order by
514:Group by
470:Keywords
460:SQL:2023
455:SQL:2016
450:SQL:2011
445:SQL:2008
440:SQL:2006
435:SQL:2003
430:SQL:1999
403:Versions
359:COALESCE
346:COALESCE
241:pk = 100
221:Examples
214:subquery
208:keyword
622:Related
570:Prepare
216:result.
80:scholar
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729:
598:Update
577:Select
528:Insert
521:Having
500:Delete
493:Create
425:SQL-92
420:SQL-89
415:SQL-86
410:SEQUEL
352:. The
350:NULLIF
348:, and
312:HAVING
291:SELECT
248:SELECT
228:SELECT
210:EXISTS
153:SELECT
145:HAVING
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605:Where
591:Union
542:Merge
315:count
303:GROUP
260:WHERE
137:WHERE
122:uses
87:JSTOR
73:books
765:ISBN
727:ISBN
612:With
563:Over
549:Null
535:Join
507:From
486:Case
354:CASE
342:CASE
327:>
297:FROM
254:FROM
59:news
794:SQL
761:278
396:SQL
300:tab
276:tab
269:100
257:tab
233:tab
225:To
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133:in
129:or
124:SQL
42:by
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309:dk
306:BY
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237:pk
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