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The Expression Builder helps users enter and validate SQL expressions (such as constrains for filters). An expression is a SQL statement or clause that transforms data or specifies a restriction. Expression Builder displays the available columns, provides a selection of functions and commonly used operators, and validates expressions.
Expression Builder has the following components:
Attributes tab: Lists attributes (columns) in the source data. Double-click an attribute to insert it into the query that you are constructing in the Expression box. at the current character position, or to replace selected characters.
Functions tab: Lists commonly used SQL Functions, divided into folders. Expand a folder to list the functions. Double-click a function to insert it into expression at the current character position, or to replace characters that you selected.
Expression box: The expression is displayed in this box as it is created. You can type into the box or you can add Attributes or Functions by double -clicking them in the Attributes tab, the Functions tab. To add an operator, click it.
Commonly-used operators are below the Expression box in the form of buttons. Click the appropriate button to insert < (less than), > (greater than), <= (less than or equal to), > = (greater than or equal to), != (not equal to), = (equal to), Or (logical OR), And (logical AND), comma (, ), ||, +, -, * (multiply), / (divide), or % into the expression at the current character position. If you prefer, you can type an operator directly into the Expression box.
Validation Results text area (read-only) and Validate: Click Validate to validate the expression in the Expression box. The results appear in Validation Results.
When you have finished creating the expression, click OK to return to the calling window. Data Miner validates the expression.