SQL top plays an important role in the advanced operations of the database, which is explained in this article.
TOP clause
The TOP clause is used to specify the number of records to return.
The TOP clause is useful for large tables with thousands of records.
Note: Not all database systems support the TOP clause.
Syntax for SQL Server:
SELECT TOP number|percent column_name (s)
From table_name
The SQL SELECT TOP in MySQL and Oracle is equivalent
MySQL syntax
SELECT column_name (s) from Table_namelimit number
Example
SELECT *from Personslimit 5
Oracle syntax
SELECT column_name (s) from Table_namewhere ROWNUM <= number
Example
SELECT *from personswhere ROWNUM <= 5
SQL TOP Instance
Now, we want to select the first two records from the "Persons" table above.
We can use the following SELECT statement:
SELECT TOP 2 * from Persons
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