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The CORRECT option is (a) .my.cnf

The best I can explain: Under Unix, an option file is set up by creating a file named ‘~/.my.cnf’ in the home directory. ‘C:\my.ini’ is the option file that is setup in WINDOWS. An option file stores the connection parameters.

The correct choice is (a) True

The best explanation: Every TIME MYSQL is invoked, connection parameters like hostname, username and password are REQUIRED. To save typing these parameters all the time, they can be saved in an option FILE instead and executed when setting up the connection.

Right answer is (a) -t

The explanation: MySQL produces OUTPUT in tab-delimited FORMAT when it is run in BATCH mode. Suppose a table-format output is desired, the -t option is used along with the mysql command. -tf is not a valid option.

The correct choice is (d) chmod +x run_me.sh

For explanation: The command ‘chmod +x file_name’ MAKES a SCRIPT FILE executable. MYSQL supports reading from a script file and executing queries from it. Before a script is RUN, it is necessary for it to be made executable.

Right ANSWER is (a) True

The explanation: MySQL is capable of reading input from a FILE in batch MODE. This is also known as the non-interactive mode. A lot of TYPING and time can be saved when commands are stored in a file and EXECUTED from a file.

The correct choice is (c) undoes last change

For explanation: Control-_ undoes the last change that was made. This can be REPEATED. The mysql INPUT editor has a VARIETY of COMMANDS to facilitate editing while providing inputs to the command LINE itself.

The correct OPTION is (a) Ctrl-A

For explanation I would SAY: Control-A moves the cursor to the beginning of the line. Ctrl-E moves the cursor to the end of the line. Control-D deletes the CHARACTER under the cursor whereas Esc-a is not VALID.

The correct choice is (a) True

Explanation: The ‘SHOW DATABASES’ command is used to DISPLAY the LIST of the databases that are being managed by the server to which connection is ESTABLISHED. This list WOULD vary from server to server.

Right OPTION is (a) DESCRIBE tbl_name

To elaborate: The ‘DESCRIBE’ command is issued to SEE the structure of the table ‘tbl_name’. It SHOWS the structure in the FORMAT: Field-Type-Null-Key-Default-Extra. The ‘VIEW’ and ‘SELECT’ commands are used to see the CONTENTS of the table.

Correct choice is (d) date and time

The BEST explanation: SELECT NOW() is an SQL query. It SHOWS both the current date and the current time. It is generally DISPLAYED in the format ‘yyyy-mm-dd hh-mm-ss’. For EXAMPLE, 2009-04-21 11-51-36.

The correct answer is (b) -P

Best explanation: The COMMAND ‘mysql -p’ (ALTERNATIVE FORM: –password) prompts for the password. ‘-h’ (alternative form: –host) specifies the host where the MySQL SERVER is running. ‘-u’ is for specifying the username.

The correct ANSWER is (B) False

For EXPLANATION: MySQL operates using a client/server ARCHITECTURE. It is the server that runs on the machine and not the client. The clients CONNECT to the MySQL server to request information from the database(s).

Correct ANSWER is (d) ORDER BY

The explanation is: An ‘ORDER BY’ clause specifies the sort order. The data is SORTED in ascending order by DEFAULT. To sort in descending order, the keyword DESC is APPENDED to the ‘ORDER BY’ clause. ‘GROUP BY’ is used to group the query RESULTS according to the criteria.

Correct answer is (d) null

For explanation: In MySQL, NULL is not comparable to other known values. It will RESULT in a NULL when COMPARED to any value. The following STATEMENT would result in four NULLS: ‘SELECT NULL = 0, NULL < 0, NULL <> 0, NULL > 0’.

The correct ANSWER is (b) unknown value

The EXPLANATION is: The NULL value in MYSQL is a SPECIAL value. It represents ‘no value’ or an ‘unknown value’. A NULL value can’t be compared like NORMAL known values since it gives undesirable results.

Right answer is (C) DIV

The EXPLANATION is: The operator ‘DIV’ is used to perform integer divisions in MySQL. ‘//’ is used in languages like Python to do the same. The operator ‘/’ performs FLOATING point divisions and ‘\’ is FACILITATES escape sequences.

The correct option is (c) information_schema

Easy explanation: After installation of MySQL, ‘information_schema’ is the special DATABASE that always exists. ‘mysql’ can be SEEN depending on ACCESS RIGHTS. It holds the grant tables. ‘sampdb’ and ‘readme_db’ do not exist by default.

The correct option is (a) LIKE

For explanation I WOULD say: The ‘LIKE’ CLAUSE filters information that match a GIVEN PATTERN. ‘WHERE’ clause selects information that is specified by a condition. ‘IS’ is used to match the exact condition specified.

Right option is (d) mysqld

Best explanation: mysqld is the MYSQL server program. It serves the incoming client REQUESTS by accessing the database. The others are not VALID MySQL programs. MySQL IMPLEMENTS a client/server architecture WHEREIN mysqld is the server program.

Correct ANSWER is (b) MYSQL server

To explain: MySQL uses client-server architecture. The MySQL server program RUNS on the machine where databases are stored. SQL is a QUERY language used for querying the tables and information retrieval.

Correct ANSWER is (a) SQL

Explanation: SQL is the standard language for RDBMS systems like MYSQL. SQL queries facilitate QUICK information retrieval from tables and other ELEMENTARY operations required to MAINTAIN an RDBMS system.

Correct answer is (b) Row

The EXPLANATION: Each row in a table represents a record. A TUPLE is a collection of attribute values that MAKES a record unique. A tuple is a unique entity whereas attribute values can be duplicate in the table.

The CORRECT OPTION is (c) Column

To explain I would say: Each column in a table represents a feature (ATTRIBUTE) of a record. Table stores the information for an entity whereas a row represents a record. OBJECT has no relevance in an RDBMS.

The CORRECT answer is (c) Relational

To EXPLAIN: MySQL is a ‘relational’ DBMS. It is efficient at RELATING data in two different tables and joining INFORMATION from them. Hierarchical and Network DBMS are based on parent-child relationships of records. Object-oriented DBMS use objects to REPRESENT models.