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https://dev.mysql.com/doc/refman/8.4/en/innodb-autocommit-commit-rollback.html
mysql> START TRANSACTION; Query OK, 0 rows affected (0.00 sec) mysql> INSERT INTO customer VALUES (10, 'Heikki'); Query OK, 1 row affected (0.00 sec) mysql> COMMIT; Query OK, 0 rows affected (0.00 sec) mysql> -- Do another transaction with ...If ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-internals.html
Files are typically divided into fixed-size blocks that are compressed into variable-size blocks, which easily leads into fragmentation. This section describes some internal implementation details about compression for InnoDB tables. The ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-deadlock-example.html
Client A enables innodb_print_all_deadlocks, creates two tables, 'Animals' and 'Birds', and inserts data into each. The following example illustrates how an error can occur when a lock request causes a deadlock. Thererfore, the previous read-only ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-next-key-locking.html
If the locks set on the index records in the scanned range do not lock out inserts made in the gaps (in this case, the gap between 90 and 102), another session can insert a new row into the table with an id of 101. Just that happens in the preceding ... The so-called phantom problem occurs within a transaction when the same query produces different sets of rows at different ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-operations.html
The change buffer is not used, because there are no random-access inserts into the secondary indexes. The next row inserted into the table uses the specified value for its auto-increment column. The newly created table includes any changes applied ... Online support details, syntax examples, and usage notes for DDL operations are provided under the following topics in this ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-single-multi.html
Before the introduction of online DDL, it was common practice to combine many DDL operations into a single ALTER TABLE statement. For DDL operations that can be done online, you can separate them into individual ALTER TABLE statements for easier ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-preload-buffer-pool.html
After restarting a busy server, there is typically a warmup period with steadily increasing throughput, as disk pages that were in the buffer pool are brought back into memory (as the same data is queried, updated, and so on). You could also restore ... To reduce the warmup period after restarting the server, InnoDB saves a percentage of the most recently used pages for each buffer pool at server shutdown and restores these pages at server ...
https://dev.mysql.com/doc/refman/8.4/en/internal-locking.html
That is, you can insert rows into a MyISAM table at the same time other clients are reading from it. This section discusses internal locking; that is, locking performed within the MySQL server itself to manage contention for table contents by ...
https://dev.mysql.com/doc/refman/8.4/en/json-function-reference.html
Table 14.22 JSON Functions Name Description Deprecated -> Return value from JSON column after evaluating path; equivalent to JSON_EXTRACT(). ->> Return value from JSON column after evaluating path and unquoting the result; equivalent to ...
https://dev.mysql.com/doc/refman/8.4/en/json-modification-functions.html
JSON_INSERT(json_doc, path, val[, path, val] ...) Inserts data into a JSON document and returns the result. The functions in this section modify JSON values and return the result. JSON_ARRAY_APPEND(json_doc, path, val[, path, val] ...) Appends ...