Informix interview questions
Best Informix interview questions And Answers
The Database object is a table or a view or any other type of objects supported by Informix. The Database objects are created using a statement SQL CREATE for these types of objects, and the database objects have owners.
A large binary object which is also known as a Blob is a collection of the binary data which is stored as a single entity in a database management system. Blobs are the audio or the images or the other multimedia objects.
Informix database uses a concept which is called key-value locking. Key Value locking is used to lock the deleted row. When the server deletes a row, then the critical values in the indexes of the table are not removed immediately. Instead, each key value is marked as deleted, and a lock is placed on the critical value.
Informix 4GL is a fourth-generation database which was developed in the mid-'80s. Informix 4GL provides the flexibility to work without the use of third generation programming languages like COBOL. Informix 4GL is mostly used in developing business applications.
- Informix 4GL database can handle the NULL values as the inputs and outputs within an Informix 4GL function.
- Informix 4GL database does not require the input or output parameters when publishing or subscribing to a web service.
- Informix 4GL database clients can also process structured data such as ARRAYs and RECORDs from the other 4GL applications.
- Informix 4GL database now includes the direct support for file I/O
There are four joins in the Informix:-
- INNER JOIN
- LEFT / RIGHT OUTER JOIN
- FULL OUTER JOIN
- CROSS JOIN
- DIRTY READ: Dirty Read Reads the data without checking whether the data is committed or not. During the read, no locks are held.
- COMMITTED READ: Committed Read reads only the determined data. During the read, no locks are held.
- REPEATABLE READ: Reads only the committed data. In this read, a shared lock is held on the rows. Other sessions can get the shared locks on those rows, but no one can get an exclusive lock.
- CURSOR STABILITY