Search results
Results From The WOW.Com Content Network
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.
MySQL Workbench now uses ANTLR4 as backend parser and has a new auto-completion engine that works with object editors (triggers, views, stored procedures, and functions) in the visual SQL editor and in models. The new versions add support for new language features in MySQL 8.0, such as common-table expressions and roles.
MySQL ships with many command line tools, from which the main interface is the mysql client. [125] [126] MySQL Utilities is a set of utilities designed to perform common maintenance and administrative tasks. Originally included as part of the MySQL Workbench, the utilities are a stand-alone download available from Oracle.
You can undo the operation of removing records by using the ROLLBACK command; DELETE requires a shared table lock; Triggers fire; DELETE can be used in the case of: database link; DELETE returns the number of records deleted; Transaction log - DELETE needs to read records, check constraints, update block, update indexes, and generate redo / undo.
Database Workbench started out as a developer tool specifically for InterBase, "InterBase Workbench", initially modeled after the SQL Navigator tool for Oracle Database by Quest Software. [ 4 ] [ 5 ] During its early years, InterBase became open-source for a short while, and soon after Firebird was created as a fork from the InterBase code base .
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.
An inner join (or join) requires each row in the two joined tables to have matching column values, and is a commonly used join operation in applications but should not be assumed to be the best choice in all situations. Inner join creates a new result table by combining column values of two tables (A and B) based upon the join-predicate.
Title Authors ----- ----- SQL Examples and Guide 4 The Joy of SQL 1 An Introduction to SQL 2 Pitfalls of SQL 1 Under the precondition that isbn is the only common column name of the two tables and that a column named title only exists in the Book table, one could re-write the query above in the following form: