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https://dev.mysql.com/doc/c-api/8.4/en/mysql-affected-rows.html
It returns the number of rows changed, deleted, or inserted by the last statement if it was an UPDATE, DELETE, or INSERT. For REPLACE statements, the affected-rows value is 2 if the new row replaced an old row, because in this case, one row was ...
https://dev.mysql.com/doc/refman/8.4/en/set-operations.html
Result Set Column Names and Data Types Set Operations with TABLE and VALUES Statements Set Operations using DISTINCT and ALL Set Operations with ORDER BY and LIMIT Limitations of Set Operations SQL set operations combine the results of multiple ...
https://dev.mysql.com/doc/ndbapi/en/ndb-ndboperation.html
When using insertTuple(), you may also define the search key with setValue(). NdbOperation::insertTuple() Description This method defines the NdbOperation to be an INSERT operation. NdbOperation::read_attr() Description Read an attribute identified ...Beginning with NDB 8.0.30, NdbOperation supports an interpreted code API similar to that implemented by ...
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/glossary.html
For example, the mysqlbackup command can log into the server being backed up to insert and update data in the progress table and the history table. apply The operation that transforms a raw backup into a prepared backup by incorporating changes that ... These terms are commonly used in information about the MySQL Enterprise Backup ...
https://dev.mysql.com/doc/refman/8.4/en/encryption-functions.html
For example: INSERT INTO t VALUES (1,AES_ENCRYPT('text',UNHEX('F3229A0B371ED2D9441B830D21A390C3'))); A passphrase can be used to generate an AES key by hashing the passphrase. For example: INSERT INTO t VALUES (1,AES_ENCRYPT('text', UNHEX(SHA2('My ...Storing the string also results in slower comparisons because of the larger values and the need to take character set collation rules into ...
https://dev.mysql.com/doc/refman/8.4/en/switchable-optimizations.html
For more information, see Section 10.2.2.5, “Derived Condition Pushdown Optimization” Derived Table Merging Flags derived_merge (default on) Controls merging of derived tables and views into outer query block. The derived_merge flag controls ...
https://dev.mysql.com/doc/refman/8.4/en/create-event.html
CREATE [DEFINER = user] EVENT [IF NOT EXISTS] event_name ON SCHEDULE schedule [ON COMPLETION [NOT] PRESERVE] [ENABLE | DISABLE | DISABLE ON {REPLICA | SLAVE}] [COMMENT 'string'] DO event_body; schedule: { AT timestamp [+ INTERVAL interval] ... The ...
https://dev.mysql.com/doc/refman/8.4/en/explain-output.html
For example, it appears for EXPLAIN INSERT INTO t VALUES(10) because that is equivalent to EXPLAIN INSERT INTO t SELECT 10 FROM DUAL. For INSERT or REPLACE statements, EXPLAIN displays this value when there is no SELECT part. This can also indicate ... The EXPLAIN statement provides information about how MySQL executes ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-midpoint_insertion.html
Newly read blocks are inserted into the middle of the LRU list. This arrangement divides the LRU list into two segments, where the pages downstream of the insertion point are considered “old” and are desirable victims for LRU eviction. You can ... Rather than using a strict LRU algorithm, InnoDB uses a technique to minimize the amount of data that is brought into the buffer pool and never accessed ...The goal is to make sure that frequently ...
https://dev.mysql.com/doc/refman/8.4/en/session-state-tracking.html
(To change sessions in a load-balanced environment, it is necessary to detect whether there is session state to take into consideration when deciding whether a switch can be made.) The tracker mechanism permits applications to know when transactions ...A client can enable these trackers to receive notification of changes to its session ...