About database columns About data links

Basic Concepts 1-23 Cross-product groups You create cross-product groups to perform mathematical cross products, which are generally used to create matrix reports. Group filters Filters enable you to conditionally remove records selected by your queries. Groups can have two types of filters: ■ Oracle Reports Builder packaged filters: ■ First , to display only the first n records for the group for example, the first 5 records ■ Last , to display only the last n records for the group ■ User-created filters, using PLSQL. See also Section 2.3.6, About links versus groups Section 2.6.9, About group filters Section 1.3.2, About group above reports Section 1.3.3, About group left reports Section 2.1.8, About matrix with group reports Section 4.5.1, Creating a report Section 4.5.2, Creating a multiquery group above report Section 4.8.7, Creating a break group Section 4.8.8, Creating a matrix cross-product group

1.7.3 About database columns

A database column represents a column that is selected by the query, containing the data values for a report. For each column that you select in your query, Oracle Reports Builder automatically creates a column in the data model of your report. If you want to perform summaries and computations on database column values, you can create new columns manually in the Data Model view for summary and formula columns or by using the Report Wizard for summary columns. You can also reassign one or more columns to a group or groups you have created. In addition to the traditional column types for example, date, number, character, Oracle Reports Builder also supports graphics or images columns, which are columns whose values can be: ■ graphics or images stored directly in the database. Such a column is usually of data type LONG or LONG RAW and contains a graphics or images. In this case, specify the graphics format in the columns properties. ■ file names. The values of such a column are pointers to files stored in the operating system. In this case, specify in the columns properties that its values are file contents Read from File and the format of the files. Many graphics or images formats are supported, including BMP, CALS, CGM, GIF, JFIF, PCD, PCX, PICT, RAS, TIFF, and so on. 1-24 Oracle Reports Users Guide to Building Reports See also Section 4.8.1, Creating a query Section 4.8.5, Selecting an image from the database Section 2.3.4, About referencing columns and parameters Section 2.3.1, About summary columns Section 2.3.2, About formula columns Section 2.3.3, About placeholder columns

1.7.4 About data links

A data link or parent-child relationship relates the results of multiple queries. A data link can establish these relationships: ■ between one querys column and another querys column. ■ between one querys group and another querys group this is useful when you want the child query to know about its parents data. A data link causes the child query to be executed once for each instance of its parent group. The child query is executed with the values of the primary key used by the parent. When a report with a data link is executed, the data link is converted into a SQL clause as specified in the links Property Inspector and appended to the child query if Oracle Reports Builder is able to parse the query. Important note : If the query cannot be parsed, the query is not modified for example, Oracle Reports Builder has no way to modify how the data is fetched when the query is defined for a pluggable data source. Although links are commonly equijoins for example, WHERE DEPTNO=DEPTNO, you can create links with various SQL clauses that is, WHERE, HAVING, or START WITH and conditions. If your database has database constraints, you can create a data link that derives its SQL clause and condition from the constraints. You can view the SELECT statements for the individual parent and child queries in Oracle Reports Builder, but cannot view the SELECT statement that includes the clause created by the data link you define. Example For the report below, the following link was defined: Figure 1–12 Sample data link The default group of the master query containing the columns Order ID and Customer is the parent group; the detail query the query to which Item, Product, and Amount belong is the child query. Basic Concepts 1-25 Figure 1–13 Sample data link output See also Section 2.3.6, About links versus groups Section 2.3.5, About non-linkable queries Section 4.8.9, Creating a data link

1.7.5 About Query Builder