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This syntax may be used for the definition of a LogiView variable database access and as an argument for 'where', 'where_ent', and 'where_ent2' commands. |
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Syntax: |
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{STR_EXPR}{WHR_CMP}{EXPR} |
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Example 1: WHERE clauses with numerical expression as comparison value |
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Definition of a selection condition as argument of a 'where' command (part of the combined select instruction): where("MAT.MAX_WIDTH" >= 5*CON1) |
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Result: | ||||||||||||||||||||||
All records of the "MAT" table are selected, whose "MAX_WIDTH" field contents is greater then or equal to the expression '5*CON1' ("CON1" is a variable or constant of type integer or float). |
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Example 2: WHERE clauses with string expression as comparison value |
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Assignment to integer variable NR by using the 'sel_value' function in the action part of a decision table: NR=sel_value("Mat.ID_NO","MAT.NAME"="maho-%") |
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Result: | ||||||||||||||||||||||
The NR integer variable
is defined with the contents of the "ID_NO" field from a record
in the WRK database table. The "NAME" string field of the selected
record matches the pattern 'maho-%', i.e. a string of arbitrary size starting
with "maho-".
If more than one record exists matching this Where clause, a selection menu with all matches is displayed. |
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Example 3: WHERE clauses with logical expression as comparison value |
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Definition of the database access for the float variable F1 (in the variable declaration table):
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Result: | ||||||||||||||||||||||
Using the float variable F1, you may access the "MAX_Y" (float) field of those records in the "WRK" database table, whose "STANDARD" (logic) field contains the value TRUE. |
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The value TRUE is represented
by a ![]() |