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https://dev.mysql.com/doc/refman/8.4/en/error-message-elements.html
This section discusses how error messages originate within MySQL and the elements they contain. The MySQL server writes some error messages to its error log. These indicate issues of interest to database administrators or that require DBA action.
https://dev.mysql.com/doc/refman/8.4/en/error-message-language.html
By default, mysqld produces error messages in English, but they can be displayed instead in any of several other languages: Czech, Danish, Dutch, Estonian, French, German, Greek, Hungarian, Italian, Japanese, Korean, Norwegian, Norwegian-ny, ...
https://dev.mysql.com/doc/refman/8.4/en/explain-output.html
In the following queries, tbl_name can be used as a const table: SELECT * FROM tbl_name WHERE primary_key=1; SELECT * FROM tbl_name WHERE primary_key_part1=1 AND primary_key_part2=2; eq_ref One row is read from this table for each combination of ...
https://dev.mysql.com/doc/refman/8.4/en/explain.html
In practice, the DESCRIBE keyword is more often used to obtain information about table structure, whereas EXPLAIN is used to obtain a query execution plan (that is, an explanation of how MySQL would execute a query). The following discussion uses ...
https://dev.mysql.com/doc/refman/8.4/en/grant-tables.html
The tables_priv and columns_priv tables contain scope columns indicating tables or table/column combinations to which each row applies. Values in these columns can contain any combination of the privileges controlled by the table. The mysql system ...
https://dev.mysql.com/doc/refman/8.4/en/identifier-qualifiers.html
An unqualified name is permitted in contexts where interpretation of the name is unambiguous. A qualified name includes at least one qualifier to clarify the interpretive context by overriding a default context or providing missing context. For ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-partitions-table.html
Each row in this table corresponds to an individual partition or subpartition of a partitioned table. The PARTITIONS table has these columns: TABLE_CATALOG The name of the catalog to which the table belongs. TABLE_SCHEMA The name of the schema ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-tables-table.html
The information_schema_stats_expiry system variable defines the period of time before cached table statistics expire. If there are no cached statistics or statistics have expired, statistics are retrieved from storage engines when querying table ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-tuning.html
Most often, the internal optimizations described in InnoDB Data Storage and Compression ensure that the system runs well with compressed data. However, because the efficiency of compression depends on the nature of your data, you can make decisions ...
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. A full-text index is defined as part of a CREATE TABLE statement or added to an ...