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https://dev.mysql.com/xa-statements.html
Each XA transaction must have a unique xid value, so the value must not currently be used by another XA transaction. For this reason, gtrid values must be globally unique so that there is no ambiguity about which global transaction a given XA ... To ...
https://dev.mysql.com/alter-table-examples.html
For NDB tables, it is also possible to change the storage type used for a table or column. row *************************** Table: t1 Create Table: CREATE TABLE `t2` ( `c1` int(11) DEFAULT NULL ) /*!50100 TABLESPACE ts_1 STORAGE DISK */ ...
https://dev.mysql.com/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 23.6.1, “Partitioning Keys, ...
https://dev.mysql.com/clone-plugin-remote.html
Use the following query to check your max_allowed_packet setting: mysql> SHOW VARIABLES LIKE 'max_allowed_packet'; The following prerequisites also apply: Undo tablespace file names on the donor must be unique. To view undo tablespace file names on ... The clone plugin supports the following syntax for cloning remote data; that is, cloning data from a remote MySQL server instance (the donor) and transferring it to the MySQL instance where the cloning operation was initiated (the ...
https://dev.mysql.com/create-spatial-reference-system.html
The combination of the ORGANIZATION org_name and org_id attribute values must be unique. srs_attribute: { NAME 'srs_name' | DEFINITION 'definition' | ORGANIZATION 'org_name' IDENTIFIED BY org_id | DESCRIPTION 'description' } srid, org_id: 32-bit ...
https://dev.mysql.com/create-table-foreign-keys.html
The CONSTRAINT symbol value, if defined, must be unique in the database. NDB requires an explicit unique key (or primary key) on any column referenced as a foreign key. MySQL supports foreign keys, which permit cross-referencing related data across ...
https://dev.mysql.com/data-size.html
If it is very likely that a long string column has a unique prefix on the first number of characters, it is better to index only this prefix, using MySQL's support for creating an index on the leftmost part of the column (see Section 13.1.15, ...
https://dev.mysql.com/events-statements-current-table.html
The THREAD_ID and EVENT_ID values taken together uniquely identify the row. The value is unique for the server instance because these IDs are generated using a global counter that is incremented atomically. The table stores one row per thread ...
https://dev.mysql.com/events-waits-current-table.html
The THREAD_ID and EVENT_ID values taken together uniquely identify the row. With single-row reporting, the total number of instrumented operations is: 10 + (10 * 20) + (10 * 20 * 30) = 6210 A significant reduction in the number of instrumented ...
https://dev.mysql.com/faqs-storage-engines.html
What are the unique benefits of the ARCHIVE storage engine? A.2.1. What are the unique benefits of the ARCHIVE storage engine? The ARCHIVE storage engine stores large amounts of data without indexes; it has a small footprint, and performs selects ...
Document created the 26/06/2006, last modified the 26/10/2018
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