What is the difference between ODBC, OLE DB & JDBC?
The differences between these two data access protocols are technical, but in the most general terms, OLE DB is newer, more advanced, and compatible with a wider selection of database technologies. In addition, OLE DB is more general, in that it includes the ODBC functionality.
Technically speaking, ODBC (Open Database Connectivity) is designed to provide access primarily to SQL data in a multi-platform environment. OLE DB (Object Linking and Embedding Database) is designed to provide access to all types of data in an OLE Component Object Model (COM) environment. OLE DB includes the SQL functionality defined in ODBC but also defines interfaces suitable for gaining access to data other than SQL data.
A query generated via ODBC is functionally similar to a query generated by OLE DB. However, be aware that if you generate a query (via STATISTICA Query) using an ODBC connection, STATISTICA uses OLE DB to connect to the ODBC connection. Because there is an intermediate connection, ODBC queries may be slower than OLE DB queries.

What is Mapping Load & Apply Map ()?
Mapping Load:The mapping prefix is used on a load or select statement to create a mapping table, these tables are different from other tables. They will be stored in separate area of memory and used as mapping tables during script execution. After execution they will automatically drop.
Ex. Mapping (Load Statement/Select Statement)
Apply Map:used for mapping data from one source to another at load time.
Ex. Apply map(Map name, expr,[default expr])
Different flavors’ of Joins in QlikView?
Join is used to convert the given data and whenever we are using joins for converting data it is known ad Data Merging.
It has many types:
·         Left join
·         Right join
·         Inner join, etc

What is the difference between Join & Keep?
In case of keep both the datasets are available in QlikView's memory while in join the load statements produce only one data set from which you have to choose the columns. Also there is no concept of outer keep where as we have outer join available in case of joins.

Explain internal match function()?
Internal match fuction is used to generate data bucket of different sizes.

What do you understand by extended interval match function()?
Extended interval match function() is used for slowly changing the dimensions.

What is concatenation?
It means sequence of interconnected things i.e. any column or row which is related to each other can be connected through concatenation.

What is NoConcatenation?
NoConcatenation prefix is used to force the identical tables as two separate internal tables.

What is incremental load in Qlikview Architect?
Incremental load is nothing but loading new or changed records from the database. With the help of QVD files we can use incremental Load.

What is Circular Loop?
A circular loop is created when the relationship between two tables can be established both directly and through another third table.

What is Generic Load in QlikView?
Qlikview Generic Load is the load which is used in Qlikview for Generic database. Generic database is used in Qlikview to define the table in the     transformation step. A Generic key word is used for defining the Generic Data base in the Qlikview. For Generic table we have to need at least three fields in the table and the second last column in the arbitrary key attribute in the table and the last one is the Value for the table.
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