What is the database language responsible for query operations in the database?

The database language responsible for query operations in the database is: Data Manipulation Language DML (Data Manipulation Language), which is mainly responsible for basic operations of data, including queries and operations such as addition, deletion, and modification.

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Database language includes the following three points:

• Data definition language (DDL) and its translation program: Mainly responsible for the schema definition of data and the construction of physical access to data.

• Data Manipulation Language (DML) and its compilation (or interpretation) program: mainly responsible for basic operations of data, including query and addition, deletion, modification and other operations.

• Data control language: Mainly responsible for explaining the meaning of each control command and deciding how to execute the control command.

The database language responsible for query operations in the database is: Data Manipulation Language DML (Data Manipulation Language), through which users can implement basic operations on the database.

Operation

• ##Insert operation
  Insert data into the specified location in the database, such as Append in the database file Add records at the end, while INSERT adds records before the specified record.

• Delete operation
  Delete a group of records that no longer need to be retained in the database, such as DELETE to mark the records in the database for deletion. PACK completely clears records marked with a deletion mark. ZAP removes all records from the database file.

• Modify operations
  Modify records or database schemas, or generate new relationship schemas and records based on original data, such as Join operations and Projection operations .

• Sort operation
  Changes the arrangement of physical storage. For example, the SORT command sorts the records in the DBF file according to the specified keyword string. From a physical storage point of view, the database has changed, but from a logical point of view (or set theory point of view), the new relationships are equivalent to those before sorting.

• Retrieval operation
  Retrieve data that meets the conditions from the database, which can be a data item, a record or a group of records. For example, the BROWSE unit implements data browsing operations. SELECT selects records that meet certain conditions and ranges.

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