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https://dev.mysql.com/doc/refman/8.4/en/packet-too-large.html
You can increase this if the server needs to handle big queries (for example, if you are working with big BLOB columns). A communication packet is a single SQL statement sent to the MySQL server, a single row that is sent to the client, or a binary ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-list.html
List partitioning in MySQL is similar to range partitioning in many ways. As in partitioning by RANGE, each partition must be explicitly defined. The chief difference between the two types of partitioning is that, in list partitioning, each ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-processlist-table.html
This implementation queries active thread data from the Performance Schema rather than the thread manager and does not require a mutex. The MySQL process list indicates the operations currently being performed by the set of threads executing within ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-statement-digests.html
For example, table columns that show wait times, lock times, or index use may highlight types of queries that are inefficient. The MySQL server is capable of maintaining statement digest information. The digesting process converts each SQL ...
https://dev.mysql.com/doc/refman/8.4/en/replace.html
REPLACE [LOW_PRIORITY | DELAYED] [INTO] tbl_name [PARTITION (partition_name [, partition_name] ...)] [(col_name [, col_name] ...)] { {VALUES | VALUE} (value_list) [, (value_list)] ... | VALUES row_constructor_list } REPLACE [LOW_PRIORITY | DELAYED] ...
https://dev.mysql.com/doc/refman/8.4/en/select-into.html
INTO form of SELECT enables a query result to be stored in variables or written to a file: SELECT ... Column and line terminators can be specified to produce a specific output format. INTO DUMPFILE writes a single row to a file without any ...
https://dev.mysql.com/doc/refman/8.4/en/string-comparison-functions.html
Note Aggregate queries involving NOT LIKE comparisons with columns containing NULL may yield unexpected results. The same is true for aggregate queries involving NULL and comparisons using NOT RLIKE or NOT REGEXP. Table 14.13 String Comparison ...
https://dev.mysql.com/doc/refman/8.4/en/subqueries.html
We say that the subquery is nested within the outer query, and in fact it is possible to nest subqueries within other subqueries, to a considerable depth. The main advantages of subqueries are: They allow queries that are structured so that it is ...
https://dev.mysql.com/doc/refman/8.4/en/subquery-restrictions.html
MySQL does not support LIMIT in subqueries for certain subquery operators: mysql> SELECT * FROM t1 WHERE s1 IN (SELECT s2 FROM t2 ORDER BY s1 LIMIT 1); ERROR 1235 (42000): This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery' ... In general, you cannot modify a table and select from the same table in a ...
https://dev.mysql.com/doc/refman/8.4/en/system-schema.html
However, in most cases there are corresponding INFORMATION_SCHEMA tables that can be queried. 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 ...