This set of MySQL Database Multiple Choice Questions & Answers (MCQs) focuses on “Storage Engine Configuration”.
1. For which of these storage engines are configuration options always built?
Explanation: The configuration options for the storage engine ‘MyISAM’ are always built. The runtime options for MyISAM are also always enabled. For the others, runtime options are explicitly enabled.
2. The storage engine for which the runtime options are always enabled is ______________
Explanation: The configuration options for the storage engine ‘MEMORY’ are always built. The runtime options for ‘MEMORY’ are also always enabled. For the others, runtime options are explicitly enabled byt specifications.
3. The most important configurable resource for MyISAM is ______________
a) key cache
b) memory cache
c) time cache
d) speed cache
Explanation: For the index processing, ‘MyISAM’ manages its own key cache, which is the most important configurable resource for the MyISAM storage engine. It is used for index based retrievals and sorts.
4. Which system variable enables mysqld to keep more tables open simultaneously?
Explanation: The ‘table_cache’ stores the size of the table cache. Increasing the value enables ‘mysqld’ to keep more tables open simultaneously by reducing the number of file open and close operations.
5. xyz in the following statement is __________
CREATE VIEW xyz AS SELECT a, b FROM t;
Explanation: A ‘View’ is created in MySQL by writing the clause ‘CREATE VIEW’ followed by the view name. Then follows the list of column names of the table that are to be presented as the view.
6. abc in the following statement is ____________
CREATE VIEW xyz (abc) AS SELECT a FROM t;
a) row name
b) column name
Explanation: Column names for a view can be explicitly provided in the ‘CREATE VIEW’ clause itself. It presents the table view with the aliased column names instead of the original column names.
7. How can a view refer to multiple tables?
Explanation: In MySQL, a ‘View’ can refer to multiple tables. This makes it a lot simpler to execute the queries involving joins. When a selection is made from the view, the join is executed producing the results.
8. What is the mantissa in -1.58E5?
Explanation: In MySQL, the scientific notation for real numbers is possible. Some values are represented as floating point numbers in scientific notation consisting of a mantissa and exponent.
9. What is the precision of BIGINT?
Explanation: In MySQL, for the expressions containing only exact values that are all integers, the evaluation uses BIGINT (64 – bit) precision. MySQL evaluates expressions using exact/approximate math.
10. How many digits is the DECIMAL used for expressions containing only exact values with fractional part?
Explanation: In MySQL, for the expressions containing only exact values and where one or more values have a fractional part, the DECIMAL arithmetic is used with digits of precision equal to 65.
Sanfoundry Global Education & Learning Series – MySQL Database.
To practice all areas of MySQL Database, here is complete set of 1000+ Multiple Choice Questions and Answers.