Justify design of Qlikview?
QlikView deployments have 3 main infrastructure components:
QlikView Developer: May be a Windows-based desktop tool that’s utilized by designers and developers to form
1) a knowledge extract and transformation model and
2) to form the graphical computer program (or presentation layer).
QlikView Server (QVS) : Handles the communication between shoppers and also the QlikView applications. It hundreds QlikView applications into memory and calculates and presents user choices in real time.
QlikView Publisher: Hundreds knowledge from completely different knowledge sources (oledb/odbc, xml, xls), reduces the QlikView application and distributes to a QVS.
Because QlikView Server and Publisher have {different|totally completely different|completely different} roles and handle hardware and memory otherwise it’s thought-about a best observe to separate these 2 elements on different servers.
What’s artificial key in Qlikview and the way to avoid it?
It’s undesirable to own multiple common keys across multiple tables during a QlikView system. This might cause QlikView to use advanced keys (a.k.a. artificial keys) to come up with the connections within the system. Artificial keys square measure usually resource significant and should hamper calculations and, in extreme cases, overload anapplication. They conjointly create a document more durable to grasp and maintain. Thereare some cases wherever artificial keys cannot be avoided (e.g. Interval Match tables), but, in general, artificial keys must always be eliminated, if attainable.
- Comment the fileds in load script
- Rename the fileds in load script
- Rename the fileds mistreatment UNQUALIFY operator;
However Set analysis outlined in qlikview?
Used for set of teams. Principally utilized in arrgeted operate like add (year) used sales of current year VS last year.
What’s distinction between Straight table and pivot table?
Pivot Table –
1) A pivot table is best at grouping: you’ll be able to simply see that group A specific row belongs to, and a bunch will have a subtotal.
2) You’ll be able to conjointly show a pivot table sort of a cross table (one or many horizontal dimensions).
3) However after you type a pivot table, you’ve got to type it initial in keeping with the primary dimension, then in keeping with subsequent, etc.
You cannot type it any manner you would like.
Straight Table-
A straight table is best at typing than a pivot table: you’ll be able to sort it in keeping with any column.
But it’s not therefore smart at grouping. Subtotals aren’t attainable, for example.
Distinction between keep and joins in Qlikview?
Left Keep and Left be a part of provides identical output. the sole distinction is that Left Keep keeps the Table separate in knowledge Model, whereas Left be a part of merges the Tables that square measure joined.
What’s progressive Load?
As bismuth apps square measure expected to cope with larger and bigger amounts {of knowledge|of knowledge|of information} the quantity of your time that it takes to retrieve that data becomes a significant issue. this might result to shear volume of information or the necessity for frequent refreshes. Either way, you are doing not wish to be propulsion all of the info all of the time. What you would like to be able to do is simply pull the info that has modified, append to it the info that you just hold on away antecedently then come back to to the business of analyzing. this may scale back load on the supply information, the network infrastructure and your QlikView server.
What are Set and let and distinction between it?
SET or a LET statement is usually used to outline the variable. The SET statement is employed after you need a variableto hold the string or numeric price that’s to the correct of the Equal (=) sign.
The LET statement is employed after you ought to judge what’s to the correct of the Equal sign
e.g : set myVar=5*2 the result’s “5*2″
Let myVar=5*2 the result’s “10″
What square measure Mapping Tables?
Typically you wish to feature an additional field to a table to use a mixture of fieldsfrom completely different tables; otherwise you wish to feature a field to wash up the info structure. Qlik- read has an efficient thanks to add single fields to a table known as mapping tables. syntax — mapping ( load statement | choose statement )
applymap ( ‘mapname’, expr, [ , defaultexpr ] )
Distinction between Expression and Dimension?
Every knowledge warehouse consists of dimensions and measures. Dimensions permit knowledge analysis from varied views. for instance, time dimension might show you the breakdown of sales by year, quarter, month, day and hour. Product dimension might assist you see that product usher in the foremost revenue. Provider dimension might assist you select those business partners UN agency invariably deliver their merchandise on time. Client dimension might assist you decide the strategic set of shoppers to whom you’d prefer to extend your terribly special offers.
Justify regarding Normalized knowledge?
Well Structured kind of knowledge, that doesn’t have any repetition or redundancy of information. Its a form of relative knowledge. Its primarily utilized in OLTP reasonably stuffs Denormalized knowledge – Its an entire bunch of information with none relationship among themselves, with redundancy of information. Its primarily utilized in OLAP reasonably stuffs.
What is instrumentality?
A instrumentality object are often wont to hold multiple charts. You’ll use an instrumentality object to place multiple charts within the same box. All charts can seem within the same window however just one chart can seem active at a given time. you’ll click the chart title to modify or toggle between charts. A word of advice: Use containers with caution. They kind connected objects and may have an effect on the properties of all connected objects.
What’s Dimensions ( what’s distinction between Expression and Dimension)?
Every information warehouse consists of dimensions and measures. Dimensions permit information analysis from varied views. as an example, time dimension may show you the breakdown of sales by year, quarter, month, day and hour. Product dimension may assist you see that merchandise usher in the foremost revenue. provider dimension may assist you opt for those business partners World Health Organization continuously deliver their product on time. client dimension may assist you decide the strategic set of shoppers to whom you’d wish to extend your terribly special offers.
Make a case for concerning Normalized Data?
Well Structured variety of information, that doesn’t have any repetition or redundancy of information. Its a sort of relative information. Its in the main employed in OLTP reasonably stuffs De-normalized information – Its an entire bunch of information with none relationship among themselves, with redundancy of information. Its in the main employed in OLAP reasonably stuffs.
What’s Snow-flaking Schema?
Snowflake Schema: AN extension of the star schema by means that of applying extra dimensions to the scale of a star schema in a very relative atmosphere. Snow-flaking may be a variety of dimensional modelling; dimensions area unit hold on in multiple relative dimension tables. A snowflake schema may be a variation of the star schema. Snow-flaking is employed to boost the performance of specific queries. The schema is diagrammed with every truth encircled by its associated dimensions as in a very star schema, and people dimensions area unit additional associated with different dimensions, branching out into a snowflake pattern.
Make a case for QlikView Resident Load?
Produce a replacement logical table in QlikView, supported a antecedently loaded (resident) table.
What’s Apply Map (Mapping Tables)?
Generally you wish to feature an additional field to a table to use a mixture of fields from totally different tables; otherwise you wish to feature a field to scrub up the info structure. Qlik- read has a good thanks to add single fields to a table known as mapping tables. syntax — mapping ( load statement | choose statement ) applymap( ‘mapname’, expr, [ , defaultexpr ] )
What Is Star Schema?
A star schema is that the simplest variety of dimensional model, within which information is organized into facts and dimensions. A truth is an incident that’s counted or measured, like a procurement or login. A dimension contains reference data concerning the very fact, like date, product, or client. A star schema is diagrammed by close every truth table with its associated dimensions table. The output diagram resembles a star.
Star Schema Definition: a way of aggregating information supported a group of better-known dimensions. It stores information multi-dimensionality in a very 2 dimensional electronic database Management System (RDBMS), like Oracle.
What’s Central Link Table?
Within the event of multiple truth tables QlikView In-Memory Technology permits USA to form a central link table that solely contains the prevailing information mixtures. rather than connection the tables the event dimensions are often unified (CONCATENATED) in to 1 central Link table. This link table will then be connected back to the event measures one facet and therefore the dimension tables on the opposite.
What’s binary load?
Binary load is loading information from another QV file. as an example, you have got application A.qvw. You’ll produce another application B.qvw with script binary A.qvw. computer file where:
file ::= [ path ] name
Examples:
Binary client.qvw;
Binary c:\qv\customer.qvw;
The path is that the path to the file, either absolute, or relative to the .qvw file containing this script line.
What’s an artificial key?
It’s a field that contains all potential mixtures of common fields among tables.