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https://dev.mysql.com/doc/refman/8.4/en/limit-optimization.html
If you need only a specified number of rows from a result set, use a LIMIT clause in the query, rather than fetching the whole result set and throwing away the extra data. MySQL sometimes optimizes a query that has a LIMIT row_count clause and no ...
https://dev.mysql.com/doc/refman/8.4/en/local-variable-scope.html
Because local variables are in scope only during stored program execution, references to them are not permitted in prepared statements created within a stored program. The scope of a local variable is the BEGIN ... The variable can be referred to ...
https://dev.mysql.com/doc/refman/8.4/en/multiple-column-indexes.html
MySQL can create composite indexes (that is, indexes on multiple columns). A multiple-column index can be considered a sorted array, the rows of which contain values that are created by concatenating the values of the indexed columns. For certain ...
https://dev.mysql.com/doc/refman/8.4/en/multiple-tables.html
Given these considerations, the CREATE TABLE statement for the event table might look like this: mysql> CREATE TABLE event (name VARCHAR(20), date DATE, type VARCHAR(15), remark VARCHAR(255)); As with the pet table, it is easiest to load the initial ... The pet table keeps track of which pets you ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-table-formats.html
The third, compressed format, can be created only with the myisampack utility (see Section 6.6.6, “myisampack — Generate Compressed, Read-Only MyISAM Tables”). When you use CREATE TABLE or ALTER TABLE for a table that has no BLOB or TEXT ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-config-example.html
To create a default value section, simply add the word default to the section name. To configure them all, create an [ndbd default] section that contains a DataMemory line to specify the data memory size. To support NDB Cluster, you should update ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-database-objects.html
In addition, the maximum offset for a fixed-width column of an NDB table is 8188 bytes; attempting to create a table that violates this limitation fails with NDB error 851 Maximum offset for fixed-size columns exceeded. Some database objects such ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndb-transporter-errors.html
This section lists error codes, names, and messages that are written to the cluster log in the event of transporter errors. 0x00 TE_NO_ERROR No error 0x01 TE_ERROR_CLOSING_SOCKET Error found during closing of socket 0x02 ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-select-all.html
Note This is the name of an index, not of a column; the index must have been explicitly named when created. ndb_select_all prints all rows from an NDB table to stdout. Usage ndb_select_all -c connection_string tbl_name -d db_name [> file_name] ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-replication-backups.html
Create any databases on the replica cluster that are present on the source cluster and that are to be replicated. Important A CREATE DATABASE (or CREATE SCHEMA) statement corresponding to each database to be replicated must be executed on each SQL ... This section discusses making backups and restoring from them using NDB Cluster ...