| SQL-query
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| The SQL- query is the parent of amost search routines in databases. For all of those who don't trust our developer's skills in programming search routines, and who might have fun trying out an sql-query themselves, we left our test-tool from the developing phase simply in the Moodmixer.
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| H Warning: Die SQL-Query hasn't got any error checking- in some cases ( ie. if a query uses wrong syntax) the Moodmixer can crash! SQL-queries are done at your own risk!
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| The SQL-query can be started via the menu option [Search- SQL-query] .
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| The syntax for queries in SQL is as follows:
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| Fieldname- condition -value-logical operator
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| The following fields and values are availble:
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| as condition one can use the normal operators:
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| The can be used in strings as well as numeric fields
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| = equals
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| <> doesn't equal
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| <= is lower than or equal ( for strings it is higher in the alphabet)
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| < is lower than
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| >= is higher than or equal
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| > is higher
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| Only for string entries there are other conditions:
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| LIKE equals ( can be used with string and placeholder % )
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| NOT LIKE doesn't equal ( can be used with string and placeholder % )
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| as logical operators there are
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| AND both values have to be true at the same time
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| OR just either of those value has to be true at the same time
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| G Attention: AND-combinations have a higher associativity than OR - combinations (as in mathematics the usual precedence rules : multiplication has higher associativity than addition' - in GB: BODMAS ) !
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| A SQL-query of our search for christmas titles as in the combined search would look like this:
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| The result displays the same amount of titles !
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| So , if somebody out there has fun using SQL-queries - go ahead and check if our developers haven't made a mistake in their search routins after all!
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