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https://dev.mysql.com/doc/refman/8.4/en/multiple-column-indexes.html
MySQL can create composite indexes (that is, indexes on multiple columns). For certain data types, you can index a prefix of the column (see Section 10.3.5, “Column Indexes”). MySQL can use multiple-column indexes for queries that test all the ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-crash-recovery.html
In this case, myisamchk does not abort on some errors (such as duplicate-key errors) but instead tries to resolve them by modifying the .MYD file. This section describes how to check for and deal with data corruption in MySQL databases. If your ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-ftdump.html
Example: Suppose that the test database contains a table named mytexttable that has the following definition: CREATE TABLE mytexttable ( id INT NOT NULL, txt TEXT NOT NULL, PRIMARY KEY (id), FULLTEXT (txt) ) ENGINE=MyISAM; The index on id is index 0 ...It reads the MyISAM index file directly, so it must be run on the server host where the table is ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-repair.html
Note If you want a repair operation to go much faster, you should set the values of the sort_buffer_size and key_buffer_size variables each to about 25% of your available memory when running myisamchk. The discussion in this section describes how ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-install-linux-source.html
Building NDB Cluster from source is similar to building the standard MySQL Server, although it differs in a few key respects discussed here. This section provides information about compiling NDB Cluster on Linux and other Unix-like platforms. For ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-exclusive-to-cluster.html
NDB Cluster has the following limitations or restrictions with regard to binary logging: NDB Cluster cannot produce a binary log for tables having BLOB columns but no primary key. The following are limitations specific to the NDB storage engine: ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-performance.html
Unique hash indexes created with USING HASH cannot be used for accessing a table if NULL is given as part of the key. The following performance issues are specific to or especially pronounced in NDB Cluster: Range scans. There are query performance ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-cluster-operations.html
The cluster_operations table provides a per-operation (stateful primary key op) view of all activity in the NDB Cluster from the point of view of the local data management (LQH) blocks (see The DBLQH Block). The state column can have any one of the ...(Currently, the MySQL Server does not expose the NDB API transaction ID of an ongoing transaction.) The operation_type column can take any one of the values READ, READ-SH, READ-EX, INSERT, UPDATE, DELETE, WRITE, UNLOCK, REFRESH, SCAN, SCAN-SH, SCAN-EX, or ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-cluster-transactions.html
The cluster_transactions table shows information about all ongoing transactions in an NDB Cluster. (Currently, the MySQL Server does not expose the NDB API transaction ID of an ongoing transaction.) block_instance refers to an instance of a kernel ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-transporters.html
Notes For each running data node in the cluster, the transporters table displays a row showing the status of each of that node's connections with all nodes in the cluster, including itself. This information is shown in the table's status column, ...