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https://dev.mysql.com/doc/internals/en/determining-logging-format.html
For each statement, we must determine the logging format: row or statement. At parse time, it is detected if the statement is unsafe to log in statement format (that is, requires row format). This must be done prior to the call to ...
https://dev.mysql.com/doc/internals/en/logging-transactions-rules-for-non-committing-statements.html
(R-log-row-format) If S is to be logged in row format (that is, if S is DML and one of the following holds: (1) @@SESSION.binlog_format=ROW; (2) @@SESSION.binlog_format=MIXED and S is unsafe): Do not log row events that write to temporary tables.
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-performance-page-per-table-stats.html
By default, rows are sorted by descending total wait time (tables with most contention first). Rows Deleted The total number of rows deleted from the table. Rows Fetched The total number of rows read from the table. Rows Inserted The total number of ...Table 5.10 Per Table Statistics Dashboard NameDescription Table Name The table ...
https://dev.mysql.com/doc/x-devapi-userguide-shell-python/en/working-with-data-sets.html
Collection.find() returns a data set with documents and Table.select() respectively Session.sql() return a data set with rows. myColl = db.get_collection('my_collection') res = myColl.find('name like :name').bind('name','L%').execute() doc = ...
https://dev.mysql.com/doc/refman/8.4/en/create-view.html
The WITH CHECK OPTION clause can be given to constrain inserts or updates to rows in tables referenced by the view. For a view to be updatable, there must be a one-to-one relationship between the rows in the view and the rows in the underlying table. The WITH CHECK OPTION clause can be given for an updatable view to prevent inserts or updates to rows except those for which the WHERE clause in the select_statement is ...
https://dev.mysql.com/doc/refman/8.4/en/index-extensions.html
row *************************** id: 1 select_type: SIMPLE table: t1 type: ref possible_keys: PRIMARY,k_d key: k_d key_len: 4 ref: const rows: 5 Extra: Using where; Using index When the optimizer takes index extensions into account, it treats k_d as ... InnoDB automatically extends each secondary index by appending the primary key columns to ...
https://dev.mysql.com/doc/refman/8.4/en/index-merge-optimization.html
The Index Merge access method retrieves rows with multiple range scans and merges their results into one. If all columns used in the query are covered by the used indexes, full table rows are not retrieved (EXPLAIN output contains Using index in ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-understanding-innodb-locking.html
When a transaction updates a row in a table, or locks it with SELECT FOR UPDATE, InnoDB establishes a list or queue of locks on that row. If a second transaction wants to update a row or lock a table already locked by a prior transaction in an ...
https://dev.mysql.com/doc/refman/8.4/en/intersect.html
query_expression_body INTERSECT [ALL | DISTINCT] query_expression_body [INTERSECT [ALL | DISTINCT] query_expression_body] [...] query_expression_body: See Section 15.2.14, “Set Operations with UNION, INTERSECT, and EXCEPT” INTERSECT limits the ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-dict-obj-tree.html
The dict_obj_tree table provides a tree-based view of table information from the dict_obj_info table. This is intended primarily for use in testing, but can be useful in visualizing hierarchies of NDB database objects. This means that you must know ...