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https://dev.mysql.com/doc/refman/8.4/en/innodb-fulltext-index.html
Full-text indexes are created on text-based columns (CHAR, VARCHAR, or TEXT columns) to speed up queries and DML operations on data contained within those columns. The words are fully sorted and partitioned among the six index tables based on the ...A full-text index is defined as part of a CREATE TABLE statement or added to an existing table using ALTER TABLE or CREATE ...
https://dev.mysql.com/doc/refman/8.4/en/insert.html
Inserting a string into a string column (CHAR, VARCHAR, TEXT, or BLOB) that exceeds the column maximum length. INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE] [INTO] tbl_name [PARTITION (partition_name [, partition_name] ...)] [(col_name ...
https://dev.mysql.com/doc/refman/8.4/en/internal-temporary-tables.html
Presence of any string column with a maximum length larger than 512 (bytes for binary strings, characters for nonbinary strings) in the SELECT list, if UNION or UNION ALL is used. The TempTable storage engine provides efficient storage for VARCHAR ... In some cases, the server creates internal temporary tables while processing ...
https://dev.mysql.com/doc/refman/8.4/en/json-attribute-functions.html
The functions in this section return attributes of JSON values. An error occurs if the argument is not a valid JSON document. An empty array, empty object, or scalar value has depth 1. A nonempty array containing only elements of depth 1 or ...
https://dev.mysql.com/doc/refman/8.4/en/json-search-functions.html
An error occurs if the json_doc argument is not a valid JSON document, any path argument is not a valid path expression, one_or_all is not 'one' or 'all', or escape_char is not a constant expression. Within the search_str search string argument, the ... The functions in this section perform search or comparison operations on JSON values to extract data from them, report whether data exists at a location within them, or report the path to data within ...
https://dev.mysql.com/doc/refman/8.4/en/json-table-functions.html
This section contains information about JSON functions that convert JSON data to tabular data. JSON_TABLE(expr, path COLUMNS (column_list) [AS] alias) Extracts data from a JSON document and returns it as a relational table having the specified ...
https://dev.mysql.com/doc/refman/8.4/en/json.html
The update can use nested calls to any of the functions listed in the previous item, in any combination, as long as the input and target columns are the same. MySQL handles strings used in JSON context using the utf8mb4 character set and utf8mb4_bin ...The JSON data type provides these advantages over storing JSON-format strings in a string column: Automatic validation of JSON documents stored in JSON ...
https://dev.mysql.com/doc/refman/8.4/en/merge-table-problems.html
In some cases, differing PACK_KEYS table option values among the MERGE and underlying tables cause unexpected results if the underlying tables contain CHAR or BINARY columns. The following are known problems with MERGE tables: MERGE child tables ...
https://dev.mysql.com/doc/refman/8.4/en/monitor-innodb-mutex-waits-performance-schema.html
$> ./mysqlslap --auto-generate-sql --concurrency=100 --iterations=10 --number-of-queries=1000 --number-char-cols=6 --number-int-cols=6; Query the wait event data. A mutex is a synchronization mechanism used in the code to enforce that only one ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-storage-engine.html
MyISAM tables have the following characteristics: All data values are stored with the low byte first. MyISAM also supports the following features: Support for a true VARCHAR type; a VARCHAR column starts with a length stored in one or two bytes.