Week 7 March 8 SQL: Chronological Sort, SUBSTRing, ROUND Dynamic SQL: Host and Lexical Reference Variables Overview: Drill-down, Roll-up Reports

Chronological sort Month sequence in the calendar Order by the month’s sequence

Without Chronological Order

Length Beginning position SUBSTR captures only parts of a string

Without SUBSTR Wasted space

ROUND rounds a number to a specified number of decimal places

Without ROUND

Order by Quarter

Dynamic SQL As opposed to static SQL, dynamic SQL allows the user to specify parts of the query (i.e., column names, table names, conditions, etc.) during runtime For example (static SQL): SQL> select manufacturer_code, to_char(sales_month_97,'q'), 2 sum(sales_revenue_97), sum(sales_revenue_98) 3 from sales_97_98 4 where lower(manufacturer_code) = 'son' 5 group by manufacturer_code, to_char(sales_month_97,'q') 6 order by to_char(sales_month_97,'q'); The same columns, table and condition are used

Dynamic SQL With dynamic SQL, parts of the query can be substituted by variable names During run time, the user will specify a value for P_time_interval Lexical reference variable name Lexical reference variable designator Host variable select manufacturer_code, &P_Time_interval, sum(sales_revenue_97), sum(sales_revenue_98) from sales_97_98 where lower(manufacturer_code) = :P_manufacturer_code group by manufacturer_code, to_char(sales_month_97,'q') order by &P_Time_interval; Host variable designator

Creating a Lexical Reference Variable Create a lexical reference variable under User Parameters of the Data Model (in the Object Navigator) Select  Create

Create a User Parameter Default name Select the new parameter, right-mouse click and select Property Palette

Change the Properties Change the name Change the data type to character Assign an initial value (optional)

Insert the Lexical Reference Variables (User Parameters)

Lexical reference variables During Runtime... Host variable Lexical reference variables (default values) Host variable

Drill-Down, Roll-up Reports A drill-down report is actually two or more reports working together The top-level report is like a master record Launches a report that provides more details about the data in its current record Generally, the detail report displays information related to the master Provides details for a single record, a group of records, or the report as a whole Master report "links" to the detail report by passing parameters that control the execution of the detail Master Detail

Drill-Down Reports Master Report (Annual) Data Model 1 Parameter-list1 (Quarters) Data Model 2 Parameter-list2 Drill-down Report (Months) Data Model 2

+ =

Annual

Quarters

Months within a Quarter