0
What else can I help you with?
Can a primary key be a foreign key?
Yes, a primary key can also be a foreign key. This is known as a composite key, where one or more columns in a table are both primary keys for that table and also act as foreign keys linking to another table.
What is the condition for a key to be a foreign key?
A key is considered a foreign key if it references the primary key of another table to establish a relationship between the two tables. It enforces referential integrity, ensuring that data in the foreign key column corresponds to data in the primary key column.
What does the term foreign key mean in databases?
The foreign key is used as a reference in a table to the primary key of another table. For example: consider a table employee with id(primary key), name, address,department_id(foreign key) as its fields.Another table department with fields department_id(primary key) and dept_name. So, department_id is primary key in department table and foreign key in employee table.
What is the function of an SQL Loader?
SQL Loader is a utility used to load data from external files into an Oracle database. It can handle loading large volumes of data quickly and efficiently, and provides flexibility in mapping data from files to database tables. It is commonly used for bulk data loading tasks.
How can a Foreign Key and a Primary Key interact with each other?
In some database systems, A Foreign Key that is set on one column (the child column ) has to point to another column (the parent column ) that is indexed. The parent column could be a primary key, since a primary key creates an index. Primary keys also keep values in the parent column unique, which can ensure unique records in the parent column's table; having a unique key on the child column can further enforce unique data that links with the unique records in the parent column .
Why you need primary key and foreign key?
In sql you use primary key more than one column in a table
What is a character function in SQL?
Spongebob
In SQL what is the function of the union operator?
In SQL, the function of the union operator is to combine the result of two or more select-statements. The union operator is a very useful tool when coding SQL.
How to define a user defined function in SQL?
Not possible in SQL, but possible in many vendor-specific SQL-based languages like Oracle PL/SQL.
What does the SQL Max function do?
The "SQL Max function" is a computer programming term, which can be used in spreadsheets to give the highest value from the currently selected column.
Will newid in sql generate duplicate key?
no
What is the function of SQL compare?
SQL compare is used to compare and synchronize data bases.It can be downloaded as a piece of software.Databases can be compared by SQL compare and synchronized.
What is the function of an SQL server replication?
The function of an SQL server replication is to restrict the control that a user has. Limiting these possibilities ensures safety on networks and with untrusted users.
What are function bus system in the database?
What are the two major components of SQL What function do they serve
Can composite key has null values?
if you want composite key for using the sql use the following sql query: select distinct(col_name) from table_name where col_name is null;
What does the replace command perform in SQL?
The replace command function in SQL preforms comparisons on the collation of an input or inputs. It also replaces the text in a string of the SQL server.
Difference between sql function and sql procedure?
Function is must be return the value but procedure cannot be returned, for more information please visit the link : http://youropensource.com
