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https://dev.mysql.com/doc/refman/8.4/en/no-matching-rows.html
If you have a complicated query that uses many tables but that returns no rows, you should use the following procedure to find out what is wrong: Test the query with EXPLAIN to check whether you can find something that is obviously wrong. Select ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations-partitioning-keys-unique-keys.html
This section discusses the relationship of partitioning keys with primary keys and unique keys. The rule governing this relationship can be expressed as follows: All columns used in the partitioning expression for a partitioned table must be part ...
https://dev.mysql.com/doc/refman/8.4/en/privileges-provided.html
AUDIT_ABORT_EXEMPT Allows queries blocked by an “abort” item in the audit log filter. SKIP_QUERY_REWRITE Queries issued by a user with this privilege are not subject to being rewritten by the Rewriter plugin (see Section 7.6.4, “The Rewriter ... The privileges granted to a MySQL account determine which operations the account can ...
https://dev.mysql.com/doc/refman/8.4/en/spatial-relation-functions-mbr.html
MySQL provides several MySQL-specific functions that test the relationship between minimum bounding rectangles (MBRs) of two geometries g1 and g2. The return values 1 and 0 indicate true and false, respectively. The MBR (also known as the bounding ...
https://dev.mysql.com/doc/refman/8.4/en/stored-objects-security.html
If the account you are searching for does not exist, any objects displayed by those queries are orphan objects. Stored programs (procedures, functions, triggers, and events) and views are defined prior to use and, when referenced, execute within a ...
https://dev.mysql.com/doc/refman/8.4/en/where-optimization.html
You might be tempted to rewrite your queries to make arithmetic operations faster, while sacrificing readability. Each table index is queried, and the best index is used unless the optimizer believes that it is more efficient to use a table scan.
https://dev.mysql.com/doc/mysql-ai/9.5/en/mys-mysqlai-ml-generate-table.html
The ML_GENERATE_TABLE routine runs multiple text generation or summarization queries in a batch, in parallel. context_column: specifies the table column that contains the context to be used for augmenting the queries and guiding the text generation ...The output generated for every input query is the same as the output generated by the ML_GENERATE ...
https://dev.mysql.com/doc/connectors/en/connector-j-connp-props-debugging-profiling.html
Default Value 1024 Since Version 8.0.31 profileSQL Trace queries and their execution/fetch times to the configured 'profilerEventHandler'. logger The name of a class that implements 'com.mysql.cj.log.Log' that will be used to log messages to.
https://dev.mysql.com/doc/connectors/en/connector-j-usagenotes-last-insert-id.html
On the other hand, the getGeneratedKeys() method is scoped by the Statement instance, so it can be used even if other queries happen on the same connection, but not on the same Statement instance. getGeneratedKeys() is the preferred method to use ...
https://dev.mysql.com/doc/internals/en/select-derived.html
Derived tables is the internal name for subqueries in the FROM clause. The processing of derived tables is now included in the table opening process (open_and_lock_tables() call). Routine of execution derived tables and substituting temporary table ...