Restriction in sql, PL-SQL Programming

Restriction in SQL

Syntax:

SELECT DISTINCT StudentId

FROM IS_CALLED

WHERE Name = 'Boris'

The WHERE clause operates on the result of the FROM clause in analogous fashion to the way it operates on an arbitrary relation expression. Name = NAME ('Boris') is an open expression. The key word DISTINCT here is redundant, as it happens, because StudentId is a declared key for IS_CALLED.

Posted Date: 1/18/2013 5:24:32 AM | Location : United States







Related Discussions:- Restriction in sql, Assignment Help, Ask Question on Restriction in sql, Get Answer, Expert's Help, Restriction in sql Discussions

Write discussion on Restriction in sql
Your posts are moderated
Related Questions
Explicit Cursor Attributes The cursor variable or each cursor has four attributes: %FOUND, %ISOPEN, %ROWCOUNT, and %NOTFOUND. When appended to the cursor or cursor variable, th

Transaction Control The Oracle is transaction oriented; that is, Oracle uses the transactions to make sure the data integrity. The transaction is a sequence of SQL data manip

Using Cursor Attributes: Every cursor has 4 attributes: %NOTFOUND, %FOUND, %ISOPEN, and %ROWCOUNT. If appended to the cursor name, they return the helpful information about

LAWS / RULES - Dollo's Law                     :           Living organisms do exhibit evolutionary irreversibility or evolution is irreversible. Williston's Law

Effects of NULL in Aggregate Operator - SQL Let aggop(x) be an invocation of some aggregate operator aggop in SQL, where x is an expression (usually an open expression) to be

Cursor Variables Similar to a cursor, cursor variable points to the current row in the result set of a multi-row query. But, dissimilar a cursor, a cursor variable can be opene

PITS Depressions in secondary cell wall is called pit. A pit present on the free cell wall surface without its partner is called Blind pit. It consists of 2 parts -

Manipulating Collections Within PL/SQL, the collections add procedural power and flexibility. The biggest benefit is that your program can compute subscripts to process the spec

Declaring Records Whenever you define a RECORD type, you may declare records of that type, as the illustration shows: DECLARE TYPE StockItem IS RECORD ( item_no INTEG

Short-Circuit Evaluation When computing a logical expression, the PL/SQL uses short-circuit evaluation. That is, the PL/SQL stops computing the expression as soon as the result