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https://dev.mysql.com/doc/refman/8.4/en/ldml-collation-example.html
To add a UCA collation for a Unicode character set without recompiling MySQL, use the following procedure. If you are unfamiliar with the LDML rules used to describe the collation's sort characteristics, see Section 12.14.4.2, “LDML Syntax ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndb-api-statistics.html
The INSERT statement incremented both the ReadRowCount and TransLocalReadRowCount NDB API statistics counters, as reflected by the increased values of Ndb_api_read_row_count_session and Ndb_api_trans_local_read_row_count_session. A number of types ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-shell-tutorial-javascript-documents-modify.html
mysql-js> db.countryinfo.modify("Name = 'France'").arrayInsert("$.Airports[0]", "CDG") To delete an element from the array, you must pass to the arrayDelete() method the index of the element to be deleted. You can use the modify() method to update ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-shell-tutorial-python-documents-modify.html
mysql-py> db.countryinfo.modify("Name = 'France'").array_insert("$.Airports[0]", "CDG") To delete an element from the array, you must pass to the array_delete() method the index of the element to be deleted. You can use the modify() method to ...
https://dev.mysql.com/doc/refman/8.4/en/numeric-type-attributes.html
When you insert a value of NULL into an indexed AUTO_INCREMENT column, the column is set to the next sequence value. Inserting NULL to generate AUTO_INCREMENT values requires that the column be declared NOT NULL. If the column is declared NULL, ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-queries-myisam.html
MyISAM supports concurrent inserts: If a table has no free blocks in the middle of the data file, you can INSERT new rows into it at the same time that other threads are reading from the table. You can force new rows to be appended (and therefore ...
https://dev.mysql.com/doc/refman/8.4/en/out-of-range-and-overflow.html
In strict mode, these statements fail, and some or all the values are not inserted or changed, depending on whether the table is a transactional table and other factors. If no restrictive modes are enabled, MySQL clips the value to the appropriate ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-hash.html
You should also keep in mind that this expression is evaluated each time a row is inserted or updated (or possibly deleted); this means that very complex expressions may give rise to performance issues, particularly when performing operations (such ... Partitioning by HASH is used primarily to ensure an even distribution of data among a predetermined number of ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-table-wait-summary-tables.html
For example, columns that aggregate all writes hold the sum of the corresponding columns that aggregate inserts, updates, and deletes. They are the same as the sum of the corresponding xxx_INSERT, xxx_UPDATE, and xxx_DELETE columns. COUNT_INSERT, ...
https://dev.mysql.com/doc/refman/8.4/en/range-optimization.html
The range access method uses a single index to retrieve a subset of table rows that are contained within one or several index value intervals. The following sections describe conditions under which the optimizer uses range access. Additionally, for ...