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https://dev.mysql.com/partitioning-key.html
Partitioning by key is similar to partitioning by hash, except that where hash partitioning employs a user-defined expression, the hashing function for key partitioning is supplied by the MySQL server. NDB Cluster uses MD5() for this purpose; for ...
https://dev.mysql.com/partitioning-overview.html
All columns used in the table's partitioning expression must be part of every unique key that the table may have, including any primary key. Possible workarounds in this situation include adding the name column to the table's primary key, adding the ... This section provides a conceptual overview of partitioning in MySQL ...
https://dev.mysql.com/audit-log-file-formats.html
The MySQL server calls the audit log plugin to write an audit record to its log file whenever an auditable event occurs. Typically the first audit record written after plugin startup contains the server description and startup options. Elements ...
https://dev.mysql.com/innodb-transaction-isolation-levels.html
For locking reads (SELECT with FOR UPDATE or FOR SHARE), UPDATE, and DELETE statements, locking depends on whether the statement uses a unique index with a unique search condition, or a range-type search condition. For a unique index with a unique ... Transaction isolation is one of the foundations of database ...
https://dev.mysql.com/create-table-foreign-keys.html
NDB requires an explicit unique key (or primary key) on any column referenced as a foreign key. If the CONSTRAINT symbol clause is given, the symbol value, if used, must be unique in the database. However, the system does not enforce a requirement ... MySQL supports foreign keys, which let you cross-reference related data across tables, and foreign key constraints, which help keep this spread-out data ...
https://dev.mysql.com/mysql-cluster-option-tables.html
ndb-deferred-constraints: Specifies that constraint checks on unique indexes (where these are supported) should be deferred until commit time. The following table provides a list of the command-line options, server and status variables applicable ...
https://dev.mysql.com/mysql-cluster-params-ndbd.html
MaxUIBuildBatchSize: Maximum scan batch size to use for building unique keys. Increasing this value may speed up builds of unique keys but impacts ongoing traffic as well. NodeId: Number uniquely identifying the data node among all nodes in the ...
https://dev.mysql.com/invisible-indexes.html
For example, an index continues to be updated per changes to table rows, and a unique index prevents insertion of duplicates into a column, regardless of whether the index is visible or invisible. A table with no explicit primary key may still have ... MySQL supports invisible indexes; that is, indexes that are not used by the ...
https://dev.mysql.com/mysql-shell-tutorial-javascript-indexes-create.html
For example, the following query will perform better with an index: mysql-js> db.countryinfo.find("demographics.Population < 100") ...[output removed] 8 documents in set (0.00 sec) The createIndex() method creates an index that you can define as ...
https://dev.mysql.com/mysql-shell-tutorial-python-documents-index.html
For example, the following query will perform better with an index: mysql-js> db.countryinfo.find("demographics.Population < 100") ...[output removed] 8 documents in set (0.00 sec) The create_index() method creates an index that you can define as ...
Document created the 26/06/2006, last modified the 26/10/2018
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