Questions

A faint ring encircles Jupiter. Neptune and Uranus are also reported to show some sort of ring.

In case of Move A to B it will move whatever the value of A into B.It mean it will move numeric, alphanumeric and alphabatic value.

In case of COMPUTE B=A it will assign the value of A into B. But in case of compute only numeric value will be compute.

Cache momory is a small high-speed memory. it is used for temporary storage of data & information between the main memory and the CPU(center processing unit). The cache memory is only in RAM.

Cache memory is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. AS the microprocessor processes data, it looks in the cache memory and if it finds the data there.

A mountain is what has roots that nobody sees, Is taller than trees, Up, up it goes, Yet it never grows.

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.