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https://dev.mysql.com/insert.html
INSERT with an ON DUPLICATE KEY UPDATE clause enables existing rows to be updated if a row to be inserted would cause a duplicate value in a UNIQUE index or PRIMARY KEY. REPLACE is the counterpart to INSERT IGNORE in the treatment of new rows that ... INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE] [INTO] tbl_name [PARTITION (partition_name [, partition_name] ...)] [(col_name [, col_name] ...)] {VALUES | VALUE} (value_list) [, (value_list)] ...
https://dev.mysql.com/mysqlslap.html
--auto-generate-sql-unique-write-number How many different queries to generate for --auto-generate-sql-write-number --auto-generate-sql-write-number How many row inserts to perform on each thread --commit How many statements to execute before ...
https://dev.mysql.com/sql-mode.html
ONLY_FULL_GROUP_BY Reject queries for which the select list, HAVING condition, or ORDER BY list refer to nonaggregated columns that are neither named in the GROUP BY clause nor are functionally dependent on (uniquely determined by) GROUP BY columns.
https://dev.mysql.com/create-table-check-constraints.html
Consequently, CHECK constraint names must be unique per schema; no two tables in the same schema can share a CHECK constraint name. (Exception: A TEMPORARY table hides a non-TEMPORARY table of the same name, so it can have the same CHECK constraint ... Prior to MySQL 8.0.16, CREATE TABLE permits only the following limited version of table CHECK constraint syntax, which is parsed and ignored: CHECK (expr) As of MySQL 8.0.16, CREATE TABLE permits the core features of table and column CHECK constraints, for all storage ...
https://dev.mysql.com/innodb-locking.html
Gap locking is not needed for statements that lock rows using a unique index to search for a unique row. Shared and Exclusive Locks Intention Locks Record Locks Gap Locks Next-Key Locks Insert Intention Locks AUTO-INC Locks Predicate Locks for ...
https://dev.mysql.com/optimizing-innodb-bulk-data-loading.html
If you have UNIQUE constraints on secondary keys, you can speed up table imports by temporarily turning off the uniqueness checks during the import session: SET unique_checks=0; ... SET unique_checks=1; For big tables, this saves a lot of disk I/O ... These performance tips supplement the general guidelines for fast inserts in Section 8.2.5.1, “Optimizing INSERT ...
https://dev.mysql.com/innodb-memcached-porting-mysql.html
If there is a short numeric primary key column in an InnoDB table, use it as the unique lookup key for memcached by converting the integer to a string value. If the memcached server is used for multiple applications, or with more than one InnoDB ...
https://dev.mysql.com/structured-system-variables.html
Structured variable instances and components follow these naming rules: For a given type of structured variable, each instance must have a name that is unique within variables of that type. However, instance names need not be unique across ... A ...
https://dev.mysql.com/mysql-installer-workflow.html
The ID of each server instance within a cluster must be unique; however, you can reuse the same number in a different cluster. The ID of each server instance within a cluster must be unique; however, you can reuse the same number in a different ...
https://dev.mysql.com/mysql-cluster-mgm-definition.html
Id Table 22.9 This table provides type and value information for the Id management node configuration parameter Property Value Version (or later) NDB 8.0.13 Type or units unsigned Default [none] Range 1 - 255 Restart Type IS Each node in the cluster ... The [ndb_mgmd] section is used to configure the behavior of the management ...
Document created the 26/06/2006, last modified the 26/10/2018
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