Chapter 3 DBMS Reference Guide
This section explains the generation and reverse engineering mechanism.
The word statement is used to define a piece of SQL syntax; statements usually contain variables that will be evaluated during generation and script reverse engineering.
The word query is reserved to ODBC reverse engineering.
During generation, the statements are parsed and the variables contained in the statements are evaluated and replaced by their actual values taken from the current model. The same statements are used for script and ODBC generation.
During script reverse engineering, PowerDesigner parses the script and identifies the different statements thanks to the terminator (defined in Script\Sql\Syntax). Each individual statement is "associated" with an existing statement in the DBMS definition file in order to commit the variables in the reversed statement as items in a PowerDesigner model.
During ODBC reverse engineering, special queries are used to retrieve information from the database system tables. Each column of a query result set is associated with a variable. The query header specifies the association between the columns of the resultset and the variable. The values of the returned records are stored in these variables which are then committed as object attributes.
For more information on variables, see section "Optional strings and variables".
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