Following syntax rules apply to the search filters |
- The first line contains always the text <select where>. This formulation was based on SQL.
- The second line always begins with a left parenthesis.
- The further lines contain a filter instruction or a parenthesis.
- The last line contains the right parenthesis.
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Logical operators for filter instructions |
AND: The filter instruction of this line is AND combined with the preceding one.
OR: The filter instruction of this line is OR combined with the preceding one. |
Compare operators <, >, =, <> and compare values |
Upper-case / lower-case are ignored! <, > Number: Numeric compare of field contents and number. <, > ’Text’: Text compare of field contents and number. = Number: Test if equal. (Numeric compare) = ’Text’: Test if equal. (Text compare) = ’*Text’: Test whether the field content contains 'text'. = ’Text*’: Test whether the field content begins with 'text'. <> ’Text’: Test whether the field contents is different from 'text'. <> Number: Test whether the field content is different from Number. |
Filter Instruction (line) |
Example with two lines:
select where ( City = 'Berlin' AND Firm = '*Inc' )
- The first filter instruction to a left parenthesis begins with a field name. All further filter instructions within the same parenthesis level begin with a logical operator (AND/OR), followed from a field name.
- After the field name comes a blank, then a compare operator, then again a blank followed from the compare value.
Example with sub-parenthesis:
select where ( City = 'Berlin' AND ( Firm = '*Inc' OR Firm = '* AG.' ) )
- Subordinate clip tiers can be inserted by hand. You always begin with a logical operator (AND/OR), followed from a left parenthesis and a line wrap. (Behind a left parenthesis no further instructions must stand in the same line.)
- The following lines contain in each case a filter instruction.
- The left parenthesis is to be locked through a left parenthesis in a separate line.
- In order to increase the readability, the clip tiers should be indented as in the example. Blanks or tabulators can be used for that.
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