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Deleting all rows from a table can be very time-consuming. Some DBMS [clarification needed] offer a TRUNCATE TABLE command that works a lot quicker, as it only alters metadata and typically does not spend time enforcing constraints or firing triggers. DELETE only deletes the rows. For deleting a table entirely the DROP command can be used.
In SQL, the TRUNCATE TABLE statement is a data manipulation language (DML) [1] operation that deletes all rows of a table without causing a triggered action. The result of this operation quickly removes all data from a table , typically bypassing a number of integrity enforcing mechanisms.
Reserved words in SQL and related products In SQL:2023 [3] In IBM Db2 13 [4] In Mimer SQL 11.0 [5] In MySQL 8.0 [6] In Oracle Database 23c [7] In PostgreSQL 16 [1] In Microsoft SQL Server 2022 [2]
The DROP statement destroys an existing database, table, index, or view. A DROP statement in SQL removes a component from a relational database management system (RDBMS). The types of objects that can be dropped depends on which RDBMS is being used, but most support the dropping of tables , users , and databases .
In computer programming, create, read, update, and delete (CRUD) are the four basic operations (actions) of persistent storage. [1] CRUD is also sometimes used to describe user interface conventions that facilitate viewing, searching, and changing information using computer-based forms and reports.
Formally, a "database" refers to a set of related data accessed through the use of a "database management system" (DBMS), which is an integrated set of computer software that allows users to interact with one or more databases and provides access to all of the data contained in the database (although restrictions may exist that limit access to particular data).
A common table expression, or CTE, (in SQL) is a temporary named result set, derived from a simple query and defined within the execution scope of a SELECT, INSERT, UPDATE, or DELETE statement. CTEs can be thought of as alternatives to derived tables ( subquery ), views , and inline user-defined functions.
The DBC/1012 Data Base Computer was a database machine introduced by Teradata Corporation in 1984, as a back-end data base management system for mainframe computers. [1] The DBC/1012 harnessed multiple Intel microprocessors, each with its own dedicated disk drive, by interconnecting them with the Ynet switching network in a massively parallel processing system.