Technology Questions

An application plan or package is generated by the bind to define an access path. 

Yes the object is retained. It creates a timer that calls a selector on the current threads run loop. It may not be 100% precise time-wise as it attempts to dequeue the message from the run loop and perform the selector.

•  NO_CACHE – It is used for not caching values.


•  PRE_LOAD_CACHE – Result column preloads and compares the column into the memory, prior to executing the lookup.


•  PRE_LOAD_CACHE is used when the table can exactly fit in the memory space.


•  DEMAND_LOAD_CACHE – Result column loads and compares the column into the memory when a function performs the execution.


•  DEMAND_LOAD_CACHE is suitable while looking up the highly repetitive values with small subset of data.

The knowledge of Joins is a MUST for every interviewee. Most SQL programmers have used inner join and  outer join[left/right]; but the catch point here is to also mention cross join and self-join.

Overloading allows multiple functions to exist with same name but different parameters. Again if you take bike as an example, it has a function “Start” with two forms i.e. ’Auto Start’ and ’kick start’.

Following are the data integration factors:

- Sub set of the available data should be optimal. 

- Noise/distortion estimation levels because of sensory/processing conditions at the time of data collection.

- Accuracy, spatial and spectral resolution of data.

- Data formats, storage and retrieval mechanisms.

- Efficiency of computation for integrating data sets to reach the goals.

Trigger allows us to execute a batch of SQL code when an insert, update or delete command is executed against a specific table.

Triggers are special types of stored procedures that are defined to execute automatically in place of or after data modifications. They can be executed automatically on the insert, delete and update operation.

If you create an Aggregate with more than 16 characteristics, then we call that aggregate as FLAT Aggregate. When an aggregate is active then new data is not available for reporting,These aggregates are called Flat Aggregates.