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https://dev.mysql.com/doc/refman/8.4/en/show-parse-tree.html
SHOW PARSE_TREE select_statement SHOW PARSE_TREE displays a representation of the parse tree for the input SELECT statement, in JSON format. Note This statement is available only in debug builds, or if the MySQL server was built using ...
https://dev.mysql.com/doc/refman/8.4/en/sql-prepared-statements.html
Using prepared statements with placeholders for parameter values has the following benefits: Less overhead for parsing the statement each time it is executed. Typically, database applications process large volumes of almost-identical statements, ...
https://dev.mysql.com/doc/refman/8.4/en/statement-caching.html
For certain statements that a client might execute multiple times during a session, the server converts the statement to an internal structure and caches that structure to be used during execution. Caching enables the server to perform more ...
https://dev.mysql.com/doc/refman/8.4/en/sys-format-statement.html
Given a string (normally representing an SQL statement), reduces it to the length given by the statement_truncate_len configuration option, and returns the result. Otherwise, the middle part of the string is replaced by an ellipsis (...). This ...
https://dev.mysql.com/doc/refman/8.4/en/sys-table-exists.html
Tests whether a given table exists as a regular table, a TEMPORARY table, or a view. If both a temporary and a permanent table exist with the given name, TEMPORARY is returned. Parameters in_db VARCHAR(64): The name of the database in which to ...
https://dev.mysql.com/doc/refman/8.4/en/system-schema.html
It contains tables that store information required by the MySQL server as it runs. A broad categorization is that the mysql schema contains data dictionary tables that store database object metadata, and system tables used for other operational ...
https://dev.mysql.com/doc/refman/8.4/en/telemetry-metrics-meter-metrics.html
The following server metrics are registered by default: mysql.stats Metrics mysql.stats.com Metrics mysql.stats.connection Metrics mysql.perf_schema Metrics mysql.stats.handler Metrics mysql.stats.myisam Metrics mysql.stats.ssl Metrics mysql.inno ...
https://dev.mysql.com/doc/refman/8.4/en/temporary-table-problems.html
Temporary tables created with CREATE TEMPORARY TABLE have the following limitations: TEMPORARY tables are supported only by the InnoDB, MEMORY, MyISAM, and MERGE storage engines. Use ALTER TABLE instead: ALTER TABLE old_name RENAME new_name; You ...
https://dev.mysql.com/doc/refman/8.4/en/union.html
query_expression_body UNION [ALL | DISTINCT] query_block [UNION [ALL | DISTINCT] query_expression_body] [...] query_expression_body: See Section 15.2.14, “Set Operations with UNION, INTERSECT, and EXCEPT” UNION combines the result from multiple ...
https://dev.mysql.com/doc/refman/8.4/en/use.html
USE db_name The USE statement tells MySQL to use the named database as the default (current) database for subsequent statements. This statement requires some privilege for the database or some object within it. The named database remains the ...