157A Clauses

Question 1

SQL Create

Answer 1

CREATE DATABSE database_name;

Question 2

SQL USE

Answer 2

USE database_name;

Question 3

SQL DROP

Answer 3

DROP DATABASE database_name;

Question 4

SQL CREATE TABLE

In an SQL driven database, the data is stored in a structured manner, i.e. in the form of tables.

Answer 4

CREATE TABLE table_name(
column1 dataype,
column2 datatype,
column3 datatype);

Question 5

SQL DESC

Every table in a database has a structure of its own. To display the structure of database tables, we
use the DESC statements.

Answer 5

DESC table_name;

Question 6

SQL INSERT INTO

The SQL INSERT INTO Statement is used to insert data into database tables.

Answer 6

INSERT INTO database_name(column1, column2, column3) VALUES (data,data,data);

Question 7

SQL SELECT

In order to retrieve the result-sets of the stored data from a database table, we use the SELECT
statement.

Answer 7

SELECT * FROM database_name;

or

SELECT column1, column2,column3 FROM table_name;

Question 8

SQL UPDATE

When the stored data in a database table is outdated and needs to be updated without having to
delete the table, we use the UPDATE statement

Answer 8

UPDATE database_name SET column1 = value1, column2, value2;

Question 9

SQL DELETE

Answer 9

DELETE FROM table_name WHERE (CONDITION)

Question 10

SQL DROP TABLE

Answer 10

DROP TABLE table_name;

Question 11

SQL TRUNCATE TABLE

The TRUNCATE TABLE statement is implemented in SQL to delete the data of the table but not the
table itself.

Answer 11

TRUNCATE TABLE table_name;

Question 12

SQL ALTER TABLE

The ALTER TABLE statement is used to alter the structure of a table. For instance, you can add, drop,
and modify the data of a column using this statement.

Answer 12

ALTER TABLE table_name
{ADD|DROP|MODIFY} column_name {data_type};

Question 13

SQL DISTINCT CLAUSE

The DISTINCT clause in a database is used to identify the non-duplicate data from a column.

Answer 13

SELECT DISTINCT column1, column2…columnN FROM table_name;

Question 14

SQL WHERE CLAUSE

the WHERE clause is used to filter rows from a table by applying a condition

Answer 14

SELECT * FROM table_name WHERE age > 20;

SELECT column1, column2….columnN
FROM table_name
WHERE CONDITION;

Question 15

SQL AND/OR Operators

The AND/OR Operators are used to apply multiple conditions in the WHERE clause.

Answer 15

SELECT column1, column2….columnN
FROM table_name
WHERE CONDITION-1 {AND|OR} CONDITION-2

Question 16

SQL IN Clause

The IN Operator is used to check whether the data is present in the column or not, using the WHERE
clause.

Answer 16

SELECT column1, column2….columnN
FROM table_name
WHERE column_name IN (val-1, val-2,…val-N);

Question 17

SQL BETWEEN Clause

The BETWEEN Operator is used to retrieve the values from a table that fall in a certain range, using
the WHERE clause

Answer 17

SELECT column1, column2….columnN
FROM table_name
WHERE column_name BETWEEN val-1 AND val-2;

Question 18

SQL LIKE CLAUSE

the like operator is used to retrive the values from the table that match a cretain pattern using the WHERE clause

Answer 18

SELECT column1, column2….columnN
FROM table_name
WHERE column_name LIKE { PATTERN };

Question 19

SQL ORDER BY clause

use to arrange values in a specific order

Answer 19

SELECT column1, column2, column3 FROM table_name WHERE (CONDITION) ORDER BY column_name{ASC/DESC};

Question 20

SQL GROUP BY clause

The GROUP BY Clause is used to group the values of a column together

Answer 20

SELECT SUM(column_name) FROM table_name
WHERE CONDITION
GROUP BY column_name;

Question 21

SQL COUNT function

the COUNT function gives the number of non-null values present in the specified column

Answer 21

SELECT COUNT(column_name) FROM table_name WHERE (CONDITION);

Question 22

SQL HAVING clause

The HAVING clause is also used to filter a group of rows by applying a condition.

Answer 22

SELECT SUM(column_name) FROM table_name
WHERE CONDITION
GROUP BY column_name
HAVING (arithematic function condition);

Question 23

SQL CREATE INDEX

to create index on a database table. SQL provides the CREATE INDEX statement.

Answer 23

CREATE UNIQUE INDEX index_name
ON table_name ( column1, column2,…columnN);

Question 24

SQL DROP INDEX

used to drop an index from a table

Answer 24

DROP INDEX sample_index on CUSTOMERS;