Questions

The 106th Indian Science Congress 2019 will held in Lovely Professional University in Jalandhar, Punjab from 3rd January 2019 to 7th January 2019. PM Narendra Modi is going to inaugarate this.

In Britain few of the Canals built during the early days of the Industrial Revolution are now playing an important role in the economy  of the country. Example, Grand Union Canal.

The Egyptian scripts is known as Hieroglyphic which means 'sacred writing' . It consisted of 24 signs, each of which stood for a single consonant. Vowels were not written. Later the Egyptian started using symbols for ideas and the total number of signs rose to about 500. The writers, who constituted an important section of society , wrote with reed pens on the leaves of a plant called 'Papyrus' from which we get the word 'paper'.

A Subquery or Inner query or a Nested query is a query within another SQL query and embedded within the WHERE clause.

Subqueries are most frequently used with the SELECT statement. The basic syntax is as follows::

SELECT column_name [, column_name ]
FROM table1 [, table2 ]
WHERE column_name OPERATOR
(SELECT column_name [, column_name ]
FROM table1 [, table2 ]
[WHERE])

A subquery is used to return data that will be used in the main query as a condition to further restrict the data to be retrieved.

Subqueries can be used with the SELECT, INSERT, UPDATE, and DELETE statements along with the operators like =, <, >, >=, <=, IN, BETWEEN, etc.

There are a few rules that subqueries must follow −

1. Subqueries must be enclosed within parentheses.

2. A subquery can have only one column in the SELECT clause, unless multiple columns are in the main query for the subquery to compare its selected columns.

3. An ORDER BY command cannot be used in a subquery, although the main query can use an ORDER BY. The GROUP BY command can be used to perform the same function as the ORDER BY in a subquery.

4. Subqueries that return more than one row can only be used with multiple value operators such as the IN operator.

5. The SELECT list cannot include any references to values that evaluate to a BLOB, ARRAY, CLOB, or NCLOB.

6. A subquery cannot be immediately enclosed in a set function.

7. The BETWEEN operator cannot be used with a subquery. However, the BETWEEN operator can be used within the subquery.

CH3COOH, chemically known as Acetic acid, is not a strong acid among the given acids like Sulphuric acid, Hydrochloric acid,...