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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. All of this takes time, hence it takes time much longer than with TRUNCATE
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.
The DROP statement is distinct from the DELETE and TRUNCATE statements, in that DELETE and TRUNCATE do not remove the table itself. For example, a DELETE statement might delete some (or all) data from a table while leaving the table itself in the database, whereas a DROP statement removes the entire table from the database.
The SQuirreL SQL Client is a database administration tool. It uses JDBC to allow users to explore and interact with databases via a JDBC driver. It provides an editor that offers code completion and syntax highlighting for standard SQL.
The format used is determined by the user when creating the table. [29] Rowstore tables, as the name implies, store information in row format, which is the traditional data format used by RDBMS systems. Rowstores are optimized for singleton or small insert, update, or delete queries and are most closely associated with OLTP (transactional) use ...
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.
Data manipulations (INSERT, UPDATE, DELETE) may be done from a spreadsheet-like interface. Both raw table data and a result set from a query can be manipulated. Visual Schema Designer; Visual Query Builder; Query Formatter; Connectivity options: Direct client/server using MySQL API (SSL supported), HTTP/HTTPS tunneling, SSH tunneling
Each MyISAM table is stored on disk in three files (if it is not partitioned). The files have names that begin with the table name and have an extension to indicate the file type. MySQL uses a .frm file to store the definition of the table, but this file is not a part of the MyISAM engine; instead it is a part of the server.