Principle of customized SQL access types

Customizing SQL access types consists in either modifying a standard access type or creating a nonstandard access type. For example, you can customize an access type to select only the customers who put in an order that amounts to more than $50.

You can customize SQL accesses as follows:
  • Add or replace clauses in a standard access type. To do so, you can modify the standard access type or associate the standard access type with a nonstandard access type.
  • Create an SQL access type by coding a nonstandard access type.
  • Implement extraction criteria that correspond to extraction methods. An extraction method is a particular selection that is requested upon a selection service of a Business Component.
Note: You must be familiar with the SQL syntax before customizing SQL accesses.

Implementing customized standard access types is automatic or almost automatic whereas implementing nonstandard access types must be requested with specific code. So you choose between customizing a standard access type or a nonstandard access type according to how often this access is to be used in Programs, Screens, or Business Components.

To implement customized access types, complete the following steps:
  1. Describe customized access types in the GG Lines of Segments.
    Note: If an extraction method is to be used, you must also select the Data Elements that constitute the selection parameters of the extraction method. To do so, in the Logical View -CE Lines, select E in the Data type field of each Data Element that constitutes a selection parameter.
  2. Implement or ignore the described customized access types. You can implement them in a Program only, or implement only some of them. You are free to use them as you need.
    • To implement the customized access types, except the access types of extraction methods, you must call the SQL micropattern in the COBOL source code of the entities (Program, Screen, or Business Component) that call this Segment. You can also insert the corresponding snippet for a guided input.
    • To implement the customized access types of extraction methods, you must call the ££80EX protected Macro in the Business Component -CP Lines and specify the values of its parameters. The extraction methods that are implemented in another way are ignored. In this case, a warning is automatically displayed in the COBOL code.
  3. Generate the Program, Screen, or Business Component that contains the customized access types.

    For example, if a micropattern XR XX00 (where XX00 is a Segment) is inserted in a Screen and if the R access type is customized in the -GG Lines of Segment XX00, the Screen must be generated again to recognize the customized access type.


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