Register
Webpage for Databases:

Recent questions tagged databases

5 votes
2 answers
2465
ISRO2009-72
Purpose of 'Foreign Key' in a table is to ensure Null Integrity Referential Integrity Domain Integrity Null and Domain Integrity
Purpose of 'Foreign Key' in a table is to ensureNull IntegrityReferential IntegrityDomain IntegrityNull and Domain Integrity
User Avatar
1 votes
3 answers
2466
UGC NET CSE | December 2015 | Part 2 | Question: 20
A relation R={A,B,C,D,E,F,G} is given with following set of functional dependencies: F={AD→E, BE→F, B→C, AF→G}. Which of the following is a candidate key? A AB ABC ABD
A relation R={A,B,C,D,E,F,G} is given with following set of functional dependencies: F={AD→E, BE→F, B→C, AF→G}. Which of the following is a candidate key?AABABCAB...
User Avatar
3 votes
1 answer
2467
DB basics SQL
The maximum length of an attribute of type text is 127 255 256 It is variable
The maximum length of an attribute of type text is127255256It is variable
User Avatar
1 votes
1 answer
2468
DB \ relational algebra
User Avatar
0 votes
2 answers
2470
Let me know <concept > for output of nested aggregation function as : select max(min(price)) from Products ?
I have read in theory that multiple aggregation = innermost aggregation ,So I was expecting result as min(price)BUTwhen I run this program on www.w3school.com <SQL ...
User Avatar
0 votes
1 answer
2471
er
User Avatar
1 votes
1 answer
2472
ddl
User Avatar
1 votes
0 answers
2475
database
Suppose block hold either 3 records or Ten (key ,pointers ) pairs .As a function of n , the number of records . How many block do we need to hold a data file and dense index ? a) 10n/30 b) 11n/3 c)n/3 d) 13n/30
Suppose block hold either 3 records or Ten (key ,pointers ) pairs .As a function of n , the number of records . How many block do we need to hold a data file and dense in...
User Avatar
8 votes
5 answers
2478
ISRO-2013-61, ISRO2008-35
Embedded pointer provides A secondary access path A physical record key An inverted index A primary key
Embedded pointer providesA secondary access pathA physical record keyAn inverted indexA primary key
User Avatar
0 votes
0 answers
2479
Indexed Sequential File
Can anyone explain Indexed Sequential File with , with respect to Cylinder and track number .I am unable to visualize
Can anyone explain Indexed Sequential File with , with respect to Cylinder and track number .I am unable to visualize
User Avatar
0 votes
1 answer
2480
File Processing
Can anyone give me an example of fixed length records and variable length records with respect to any Relational table .? I dont want definition of these terms .
Can anyone give me an example of fixed length records and variable length records with respect to any Relational table .?I dont want definition of these terms .
User Avatar
0 votes
2 answers
2481
Transaction processing
W1(X)R2(Y)R1(Y)R2(X) ? Is it view Serializable or Conflict or both ?
W1(X)R2(Y)R1(Y)R2(X) ?Is it view Serializable or Conflict or both ?
User Avatar
0 votes
1 answer
2483
SQL
what is the difference b/w following two query:- SELECT distinct R.* FROM R,S where R.a = S.a; SELECT R.* FROM R,(select distinct a from S) as S1 where R.a = S1.a; a is attribute and ***duplicate*** tuples are allowed
what is the difference b/w following two query:-SELECT distinct R.*FROM R,Swhere R.a = S.a;SELECT R.*FROM R,(select distinct a from S) as S1where R.a = S1.a;a is attribut...
User Avatar
3 votes
1 answer
2484
SQL QUERY
what is the meaning of following query: select R.* from R,S where R.a = S.a and is unique R;
what is the meaning of following query:select R.* from R,S where R.a = S.a and is unique R;
User Avatar
8 votes
2 answers
2485
ISRO-2013-27
The physical location of a record determined by a formula that transforms a file key into a record location is Hashed file $B$-Tree file Indexed file Sequential file
The physical location of a record determined by a formula that transforms a file key into a record location isHashed file$B$-Tree fileIndexed fileSequential file
User Avatar
26 votes
3 answers
2489
GATE CSE 1992 | Question: 13b
Suppose we have a database consisting of the following three relations: ... are liked by each customer. Express the following query in relational algebra: Print the hotels the serve the snack that customer Rama likes.
Suppose we have a database consisting of the following three relations:$$\begin{array}{|c|c|} \hline \text {FREQUENTS} & \text {(CUSTOMER, HOTEL)} \\\hline \text {SERVES}...
User Avatar
Page: