What is a lookup table in Informatica?
What is a lookup table in Informatica?
Lookup transformation is used to look up a source, source qualifier, or target to get the relevant data. It is a kind of join operation in which one of the joining tables is the source data, and the other joining table is the lookup table.
What is lookup table function?
A lookup table is an array of data that maps input values to output values, thereby approximating a mathematical function. Given a set of input values, a lookup operation retrieves the corresponding output values from the table.
What is lookup table in database?
This type of lookup table works with databases and unloads data from them by using SQL query. Database lookup table reads data from the specified database table. Remember that Database lookup table allows to work with duplicate records (multiple records with the same key value). …
Is lookup an active or passive transformation?
When you configure the Lookup transformation to return a single row, the Lookup transformation is a passive transformation. When you configure the Lookup transformation to return multiple rows, the Lookup transformation is an active transformation. You can use multiple Lookup transformations in a mapping.
What is the difference between connected and UnConnected lookup?
Connected lookup receives input values directly from mapping pipeline, whereas UnConnected lookup receives values from the lookup expression from another transformation. Connected lookup caches all lookup columns, whereas UnConnected lookup caches only the lookup output and lookup conditions.
What is the need for a lookup table?
In computer graphics, lookup tables are used to store the starting addresses of each line and the values corresponding to the placement of pixels within a byte.
Is lookup active transformation?
Why are lookup tables used?
In data analysis applications, such as image processing, a lookup table (LUT) is used to transform the input data into a more desirable output format. A classic example of reducing run-time computations using lookup tables is to obtain the result of a trigonometry calculation, such as the sine of a value.
