Oracle Essbase 9 Implementation Guide- P70 docx

Essbase nested coding style examplesHere is a representative example of the nested coding style and the obvious benefits of employing such a method or style.. Initialize the API Login t

Essbase nested coding style examples

Here is a representative example of the nested coding style and the obvious benefits

of employing such a method or style

Begin action 1

Begin action 2

Begin action 3

Perform action 3

End action 3

Begin action 4

Perform action 4

End action 4

End action 2

End action 1

This example should illustrate nicely why the nested style is the preferable code

writing style The next example will now put the previous example into Essbase

functionality context so it makes sense for you Most Essbase API functions usually must be started or opened and after completion of the task they must be ended

or closed

Initialize the API

Login to a server

Connect to a database

Open a database outline

Browse the outline

Close the outline

Open a report

Modify & save the report

Close the report

Disconnect from a database

Logout from the server

Terminate the API

Typically, the group of Essbase API calls or functions illustrated in the previous

example would be embedded in a VB subroutine so that it would actually look

more like this:

Sub BrowseOutlineAlterReport()

Initialize the API

Login to a server

Connect to a database

Open a database outline

Browse the outline

Close the outline

Close the report

Disconnect from a database

Logout from the server

Terminate the API

End Sub

As you can see each Essbase API call has an ending or terminating call that must

be executed when the desired function has completed

Many code editors support the nested coding style by automatically indenting the next line of written code to the same indentation

as the previous line making nested code writing even easier The Visual Basic editor supports nested code writing and Oracle Essbase recommends you use the nested coding style when coding Essbase API functions

Essbase API function declarations

For your convenience your Essbase package comes with a VB code module that has all of the Essbase API functions and declarations already coded for you All you need

to do is add the module to your VB/VBA/COM+ project then start coding the API

calls and functions The file's name is esb32.bas and is a wonderful time saver

As you can see in the previous screenshot, the Essbase supplied API declaration

module includes all of the necessary global variables and other API related

structures, as well as all of the API function calls What a nice thing to have!

How to code an API function

In the following example, we will code an Essbase API function that returns

database information into an Essbase private type structure named DBINFO:

Sub GetDataBaseInfo(Appname as String, DBName as String)

'Pass Application name and Database name to VB subroutine

Dim sts as ESB_STS_T 'Dimension return code variable

Dim hCtx as ESB_HCTX_T 'Dimension API handle context

Dim DbInfo as ESB_DBINFO_T 'Dimension DB information variable

sts = EsbGetDatabaseInfo (hCtx, Appname, DBName, DbInfo) 'Execute

'API function

If sts = ESB_STS_NOERR ' Test API function return code

Call DisplayDatabaseInformation 'Branch to new subroutine on

'satisfactory return code

End If

End Sub

After a successful call to the Essbase API EsbGetDatabaseInfo function, the DbInfo

structure will be populated with a variety of database information for the database

that was passed to the function The following is an example of the variable structure showing what database information is returned

Type ESB_DBINFO_T

DataFileCacheSetting As Long 'Data File Cache size database

AppName As String * ESB_APPNAMELEN 'application name

Country As String * ESB_MBRNAMELEN 'country dimension

Category As String * ESB_MBRNAMELEN 'category dimension

CrPartition As String * ESB_MBRNAMELEN 'curr partition member

connected

End Type

There sure is a lot of information passed back from this call Now do you remember back a little bit that the variable name used in this API call is DbInfo? Yes, the

variable DbInfo, dimensioned using the variable structure above, now contains all

of the data that is listed in the ESB_DBINFO_T structure

To read any of the information returned in this structure, the steps are very easy

For instance, if you want to read how many users are connected to the database you returned the information from just code: variable = DbInfo.nConnects and your variable will now contain the number of users connected to the database You can

also use DbInfo.nConnects elsewhere in your program depending on how you

dimensioned it

Essbase API code sample blocks

It seems that for most good programmers, the only difference between programming languages is the syntax of the code itself Let's face it, logic is logic, and If means

If and End If means End If in all programming languages The syntax may vary

though, as we've all seen End If or End-If or ENDIF

You have probably sensed that Oracle has created quite a product with Essbase and you are correct You have probably also gotten the idea that Oracle is very thorough and has prepared well written and easy to understand system documentation Well, we'd have to say you are correct once again The following is a picture of a typical

API function reference found in the Oracle Essbase API Reference that can be found online or accessed through the EAS tool

The following example is an exact representation of how the Essbase API Function

Reference looks, when accessed through EAS It also looks very similar when

accessed through the Internet