What are primary keys and foreign keys?
Answers were Sorted based on User's Feedback
Answer / nevual
Primary keys are the unique identifiers for each row. They
must contain unique values and cannot be null. Due to their
importance in relational databases, Primary keys are the
most fundamental of all keys and constraints. A table can
have only one Primary key.
Foreign keys are both a method of ensuring data integrity
and a manifestation of the relationship between tables.
| Is This Answer Correct ? | 7 Yes | 0 No |
Answer / sudarsan
Primary key is a unique id for each table. This prevents
duplication of records. Each table can have a single
primary key. They can be refrenced by any tables as a
foreign key.
| Is This Answer Correct ? | 4 Yes | 0 No |
Answer / jai prakash chauhan
Primary keys are by default clustered index.
| Is This Answer Correct ? | 3 Yes | 2 No |
• Primary Key: A unique identifier for a table’s record (e.g., id in a table).
• Foreign Key: A column in a table that refers to the primary key of another table, establishing a relationship between tables.
| Is This Answer Correct ? | 0 Yes | 0 No |
please differentiate between delete and truncate?
How do I completely remove sql server instance?
What is the native system stored procedure to execute a command against all databases?
What is the basic difference between clustered and a non-clustered index?
What are data files?
1.what is the diff between nolock optimizer and read uncommitted isolation? 2.what is the diff between revoke and deny? 3.what is percieved down time? 4.whether password protection are required for backups?if yes why?if no why? 5.what is fill factor? 6.what is cost analysis? 7.what is mean by piece meal restore? 8.what is 'rowguidcol'? 9.impersonate permission? 10.what is selectivity?
default databases available in sql server and there uses ?
What is scan table/view and seek table/view when its occurs? : sql server database administration
select names starts with a,b,c
8 Answers Scope International,
Selet all the data from table where last name is n of employee
How ssrs maintain security?
What is the difference between indexing and hashing?
Oracle (3259)
SQL Server (4518)
MS Access (429)
MySQL (1402)
Postgre (483)
Sybase (267)
DB Architecture (141)
DB Administration (291)
DB Development (113)
SQL PLSQL (3330)
MongoDB (502)
IBM Informix (50)
Neo4j (82)
InfluxDB (0)
Apache CouchDB (44)
Firebird (5)
Database Management (1411)
Databases AllOther (288)