PDF (US Ltr)
- 43.3Mb
PDF (A4)
- 43.4Mb
Man Pages (TGZ)
- 297.2Kb
Man Pages (Zip)
- 402.4Kb
Info (Gzip)
- 4.3Mb
Info (Zip)
- 4.3Mb
Search Results
https://dev.mysql.com/doc/refman/8.0/en/show-databases.html
SHOW {DATABASES | SCHEMAS} [LIKE 'pattern' | WHERE expr] SHOW DATABASES lists the databases on the MySQL server host. The LIKE clause, if present, indicates which database names to match. You see only those databases for which you have some kind of ...The WHERE clause can be given to select rows using more general conditions, as discussed in Section 28.8, “Extensions to SHOW ...
https://dev.mysql.com/doc/refman/8.0/en/statement-optimization.html
The core logic of a database application is performed through SQL statements, whether issued directly through an interpreter or submitted behind the scenes through an API. The guidelines cover SQL operations that read and write data, the ...The ...
https://dev.mysql.com/doc/refman/8.0/en/stored-objects.html
This chapter discusses stored database objects that are defined in terms of SQL code that is stored on the server for later execution. Metadata changes to objects referred to by stored programs are detected and cause automatic reparsing of the ...
https://dev.mysql.com/doc/refman/8.0/en/sys-ps-check-lost-instrumentation.html
This view returns information about lost Performance Schema instruments, to indicate whether the Performance Schema is unable to monitor all runtime data. The ps_check_lost_instrumentation view has these columns: variable_name The Performance ...
https://dev.mysql.com/doc/refman/8.0/en/testing-server.html
After the data directory is initialized and you have started the server, perform some simple tests to make sure that it works satisfactorily. Use mysqlshow to see what databases exist: $> bin/mysqlshow +--------------------+ | Databases | ...This ...That enables your shell (command interpreter) to find MySQL programs properly, so that you can run a program by typing only its name, not its path ...
https://dev.mysql.com/doc/refman/8.0/en/tracing-memory-usage.html
Each stored trace is a string, which is extended (using realloc()) as optimization progresses by appending more data to it. The optimizer_trace_max_mem_size server system variable sets a limit on the total amount of memory used by all traces ...
https://dev.mysql.com/doc/refman/8.0/en/triggers.html
A trigger is a named database object that is associated with a table, and that activates when a particular event occurs for the table. The following sections describe the syntax for creating and dropping triggers, show some examples of how to use ...A trigger is defined to activate when a statement inserts, updates, or deletes rows in the associated ...Some uses for triggers are to ...
https://dev.mysql.com/doc/refman/8.0/en/update-optimization.html
The speed of the write depends on the amount of data being updated and the number of indexes that are updated. An update statement is optimized like a SELECT query with the additional overhead of a write. Another way to get fast updates is to delay ...If you do this often, it is very important to use OPTIMIZE TABLE ...
https://dev.mysql.com/doc/refman/8.0/en/window-functions-usage.html
However, whereas an aggregate operation groups query rows into a single result row, a window function produces a result for each query row: The row for which function evaluation occurs is called the current row. The query rows related to the current ...MySQL also supports nonaggregate functions that are used only as window ...
https://dev.mysql.com/doc/refman/8.0/en/performance-schema-table-characteristics.html
Many tables in the performance_schema database are read only and cannot be modified: mysql> TRUNCATE TABLE performance_schema.setup_instruments; ERROR 1683 (HY000): Invalid performance_schema usage. Privileges are as for other databases and tables: ... The name of the performance_schema database is lowercase, as are the names of tables within ...Some of the setup tables have columns that can ...Truncation is permitted to clear ...