TOP 20+ AS400 Interview Questions and Answers
1. How do you pass parameters in CL?
Using PARM keyword.
2. What are the valid user defined data area types?
CHAR, NUMERIC and LOGICAL
3. What is Multi-format logical file?
Logical which uses fields from two or more physical files.
4. What is the Select and Omit criteria in logical file?
This is used to specify rules for the Selection/Omission of records from a Physical File.
5. Can fields be concatenated INa logical file level?
Yes. by using CONCAT keyword
6. When would the ALL keyword be used?
Use with Select or Omit, to select/omit records.
7. What are the different types of keywords in display files?
File level, Record format level, Field level
8. What is difference between CAT, TCAT, BCAT?
CAT – Concatenate two variables or constants into one continuous string.
BCAT – Truncates all trailing blanks in the first character string, one blank is inserted, then the two character strings are concatenated.
TCAT – Truncates all trailing blanks in the first character string, the two character strings are concatenated.
9. What is the difference between SFLCLR and SFLINZ?
SFLCLR : It clears the subfile. SFLINZ : First it clears the subfile and initiliazing the numeric variables with zeros and alphanumeric variables with characters.
10. What is the purpose of the following?
A CSRLOC (F1ROW F1COL)
Ans:Using this record level keyword, you can specify cursor location on an output operation to the record format you are defining. The program sends output after setting the cursor location.
11. How can you detect and handle a record lock situation?
If you try to read the locked record, we can get system defined message i. e. , the program will ended abnormally. With the help of File Information Data Structure we can handle record lock situation. Generally it will happen, when the same file of type ” U” used in different programs.
12. What is the difference between array and a multiple occurrence data structure?
The values stored in array don’t vary. In the other hand, we can store the Different values in same variables at various stages.
13. What is the use of Header Specification in RPG/400?
It identifies by H in column 6, provides informaion about generating and running programs.
14. What are Control level indicators?
L1 to L9 used to identify certain fields on control fields and then used to condition which operations are to be processed at detail or total calculation or output time.
15. What is difference between fully procedural file and primary file?
In primary file the records will be read and processed from begining to end. This order is not changed. In fully procedural file the records will be read and processed in any order. The logic flow is controlled by the opcodes in RPG program.
16. What is the difference between externally described file and program described file?
The field definitions and descriptions are defined out side of the program in a externally described file. The field definitions and descriptions are defined in side the program in a program described file.
17. What is the purpose of FRCDTA (Force Data) keyword?
Use this record-level keyword to immediately display a record format, without waiting for the next input or output/input operation.
18. What is the purpose of SFLFOLD and SFLDROP keywords?
1.SFLFOLD: To fold the second line of multiple line subfile.
2.SFLDROP: To drop the second line of multiple line subfile.
19. What is the difference between array and a multiple occurrence data structure?
The values stored in array don’t vary. In the other hand, we can store the different values in same variables at various stages.
20. What is the difference between access path and Dynamic select?
Dynamic select occurs whenever the program reads file. But access path occurs before the file is read (but not necessarily). Because access path maintenance performed on the file.
21. Why would you prefer OPNQRYF than logical file?
The main difference is : Logical file creates permanent object on the system. OPNQRYF creates temporary access path.
22. What is purpose of declarative statement DEFN?
Depends on the factor 1 value it will do two things:
* If the factor1is *LIKE then DEFN opcode defines the new field based on the attributes old field. * If the factor 1 is *NAMVAR then DEFN opcodes defines the field as a data area.