DELETE TOP command in SQL Server

The DELETE TOP command in SQL Server is used to delete records from a table in SQL and limits the number of records based on an existing value or percentage.

DELETE TOP command syntax

 DELETE  TOP (giatri_dau) [PERCENT] 
 FROM bang 
 [WHERE dieu _kien]; 

Variable name or variable value

state

Table wants to delete records from there.

WHERE dieu_kien

Option. The condition that the record must meet to be deleted.

TOP (giatri_dau)

This command will delete the first row in the result set based on giatri_dau. For example, TOP (10) will delete the top 10 that meet the criteria.

PERCENT

Option. If specified, the first rows are based on the percentage of giatri_dau of the result set. For example, TOP (10) PERCENT will insert 10% of the first value in the result set.

Note

There is no need to list all fields in the DELETE statement because it will delete all rows in the table.

For example - use the keyword TOP

 DELET E TOP(10) 
 FROM nhanvien 
 WHERE ho = 'Anderson'; 

In this example, the DELETE TOP command will delete the first 10 records in the table with the employee family, Anderson. If there are other records that also have the family name of Anderson, they will not be deleted.

For example - use the keyword TOP PERCENT

 DELETE TOP (25) PER CENT 
 FROM nhanvien 
 WHERE ten = 'Sarah'; 

In this example, 25% of the DELETE TOP response's delete records will be deleted. The remaining 75% will not be deleted.

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