OBIEEbeginner
OBIEE Architecture & Components
Understand the layered architecture of OBIEE — Presentation Services, BI Server, and the underlying data sources — and how a request flows through them.
OBIEE is several cooperating services, not one program. Knowing which does what is how you answer "why is this dashboard slow" and "where is that security rule enforced".
Think of a restaurant: Presentation Services is the waiter taking your order and plating the food, the BI Server is the kitchen translating "a burger" into precise cooking instructions for whichever station (grill, fryer) has the ingredients, and the physical databases are the pantries each station pulls from.
Key Concepts
1
browser
|
Presentation Services (obips) renders the UI, holds the session,
| owns the web catalog
| logical SQL
v
BI Server (nqsserver) holds the RPD, turns logical SQL
| into physical SQL
| physical SQL
v
databases2
The division of labour.Presentation Services draws dashboards and analyses, manages sessions, and stores every saved object in
the web catalog. It does not know how the data is stored.
3
The BI Server holds the repository, works out which physical tables answer a request, generates SQL for
each source, and combines the results. It does not know what a dashboard looks like.
4
Which is what makes the split useful diagnostically.
a slow dashboard with one fast analysis -> Presentation Services
or the browser
one analysis slow -> BI Server, or the
database beneath it
a user sees data they should not -> RPD data security
a user cannot see a dashboard -> catalog permissions5
The last two are different layers and are frequently confused. Catalog permissions control access to the
object; RPD security controls access to the rows.
6
Two stores, not one.
RPD binary, the metadata model. Managed with the
Administration Tool.
web catalog file-based, every dashboard, analysis and prompt,
with permissions. Managed with Catalog Manager.7
They are deployed separately and must be kept in step: a catalog referencing a subject area that a newer
RPD renamed produces analyses that no longer run.
8
Around them sits the Fusion Middleware stack. WebLogic hosts the Java components, OPSS handles security,
and the scheduler runs agents. That is why OBIEE administration involves WebLogic concepts, and why an
authentication problem is often a WebLogic realm problem rather than an OBIEE one.
9
The question this usually leads to. Trace a request end to end: browser, Presentation Services, logical
SQL, BI Server, physical SQL, database, and back. Being able to say which layer to instrument at each step
is the answer being looked for.
10
What the interviewer is probing.1. "Name the main components and what each does." Probing: the foundation. Stalls: "A
server." Moves up: BI Server for query generation, Presentation Services for the UI, Scheduler for
agents, Java host for charts and BI Publisher, with WebLogic underneath.
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2. "What does the BI Server actually do?" Probing: the central concept. Stalls: "Runs
queries." Moves up: translates a logical request against the business model into physical SQL
against one or more sources, then stitches the results.
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3. "Why is one logical query sometimes several physical ones?" Probing: the depth. Stalls:
"It is not." Moves up: fragmentation, multiple fact tables or federated sources mean the server
issues several and combines them — which is where performance surprises come from.
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4. "Where does the repository fit?" Probing: the structure. Stalls: "It stores data." *Moves
up:* it holds no data — it is the metadata defining sources, business model and presentation, and it
is what the BI Server reads.