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https://dev.mysql.com/doc/connector-j/en/connector-j-connp-props-jdbc-compliance.html
useColumnNamesInFindColumn Prior to JDBC-4.0, the JDBC specification had a bug related to what could be given as a column name to result set methods like 'findColumn()', or getters that took a String property. JDBC-4.0 clarified "column name" to ...
https://dev.mysql.com/doc/refman/8.4/en/all-subqueries.html
The expression is TRUE if table t2 contains (-5,0,+5) because 10 is greater than all three values in t2. The expression is FALSE if table t2 contains (12,6,NULL,-100) because there is a single value 12 in table t2 that is greater than 10. The ...
https://dev.mysql.com/doc/refman/8.4/en/alter-table-partition-operations.html
This includes the rules governing the relationship between any unique keys (including any primary key) that the table might have, and the column or columns used in the partitioning expression, as discussed in Section 26.6.1, “Partitioning Keys, ...
https://dev.mysql.com/doc/refman/8.4/en/charset-connection.html
For comparisons of strings with column values, collation_connection does not matter because columns have their own collation, which has a higher collation precedence (see Section 12.8.4, “Collation Coercibility in Expressions”). This includes ...
https://dev.mysql.com/doc/refman/8.4/en/fixed-point-types.html
In a DECIMAL column declaration, the precision and scale can be (and usually is) specified. Standard SQL requires that DECIMAL(5,2) be able to store any value with five digits and two decimals, so values that can be stored in the salary column range ... The DECIMAL and NUMERIC types store exact numeric data ...
https://dev.mysql.com/doc/refman/8.4/en/function-optimization.html
MySQL also determines when to evaluate functions based on types of arguments, whether the arguments are table columns or constant values. A deterministic function that takes a table column as argument must be evaluated whenever that column changes ...A function is nondeterministic if, given fixed values for its arguments, it can return different results for different ...
https://dev.mysql.com/doc/refman/8.4/en/ibd2sdi.html
Table and tablespace object IDs are also found in the id column of the mysql.tables and mysql.tablespace data dictionary tables. ibd2sdi is a utility for extracting serialized dictionary information (SDI) from InnoDB tablespace files. ibd2sdi can ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-cmp-per-index-table.html
In this context, the table data is treated as just another index, one that happens to contain all the columns: the clustered index. The INNODB_CMP_PER_INDEX and INNODB_CMP_PER_INDEX_RESET tables have these columns: DATABASE_NAME The schema ... The ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-cmpmem-table.html
The INNODB_CMPMEM and INNODB_CMPMEM_RESET tables have these columns: PAGE_SIZE The block size in bytes. Use the INFORMATION_SCHEMA COLUMNS table or the SHOW COLUMNS statement to view additional information about the columns of this table, including ... The INNODB_CMPMEM and INNODB_CMPMEM_RESET tables provide status information on compressed pages within the InnoDB buffer ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-metrics-table.html
The INNODB_METRICS table has these columns: NAME A unique name for the counter. (The _RESET columns act like the lap counter on a stopwatch: you can measure the activity during some time interval, while the cumulative figures are still available in ... The INNODB_METRICS table provides a wide variety of InnoDB performance information, complementing the specific focus areas of the Performance Schema tables for ...