EXPLAIN has output with MATCHCOLS = 0. What does it mean?

Correct Answer: DeCLarations GENerator : used to create the host language copy books for the table definitions Also creates the DECLARE table

Correct Answer: Cursor is a programming device that allows the SELECT to find a set of rows but return them one at a time Cursor should be used because the host language can deal with only one row at a time

Correct Answer: Both these are used to combine the results of different SELECT statements UNION - Selects only distinct values UNION ALL - Selects duplicate values also Syntax: SELECT column_name(s) FROM table1 UNION / UNION ALL SELECT column_name(s) FROM table2; Notice that each SELECT statement within the UNION must have the same number of columns The columns must also have similar data types Also, the columns in each SELECT statement must be in the same order

Correct Answer: Use SELECT DISTINCT in DB2 query The DISTINCT keyword can be used to return only distinct (different) values Syntax: SELECT DISTINCT column1,column2 FROM table_name;

Correct Answer: economy moves from a trough to a peak.

Explanation:

There are basically two important phases in a business cycle that are prosperity and depression. The other phases that are expansion, peak, trough and recovery are intermediary phases.

 

Expansion is a phase in which, when the economy moves from a trough to a peak. It is a period when the level of business activity surges and gross domestic product (GDP) expands until it reaches a peak.

Correct Answer: 1 Based on the lock-size given while creating the table space 2 Programer can direct the DB2 what lock-size to use 3 If lock - size ANY is specified, DB2 usually chooses a lock-size of PAGE

Correct Answer: A DB2 utility used to collect statistics about the data values in tables which can be used by the optimizer to decide the access path It also collects statistics used for space management These statistics are stored in DB2 catalog tables

Correct Answer: To insert a NULL, move -1 to the null indicator To insert a valid value, move 0 to the null indicator

Correct Answer: REORG reorganizes data on physical storage to reclutser rows, positioning overflowed rows in their proper sequence, to reclaim space, to restore free space It is used after heavy updates, inserts and delete activity and after segments of a segmented tablespace have become fragmented

Correct Answer: SELECT statement has resulted in retrieval of more than one row