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https://dev.mysql.com/create-table-secondary-indexes.html
JSON columns and indirect indexing in NDB Cluster It is also possible to use indirect indexing of JSON columns in MySQL NDB Cluster, subject to the following conditions: NDB handles a JSON column value internally as a BLOB. A secondary index defined ...
https://dev.mysql.com/create-table-select.html
For example: mysql> CREATE TABLE test (a INT NOT NULL AUTO_INCREMENT, -> PRIMARY KEY (a), KEY(b)) -> ENGINE=MyISAM SELECT b,c FROM test2; This creates a MyISAM table with three columns, a, b, and c. This is done intentionally to make the statement ... You can create one table from another by adding a SELECT statement at the end of the CREATE TABLE statement: CREATE TABLE new_tbl [AS] SELECT * FROM orig_tbl; MySQL creates new columns for all elements in the ...
https://dev.mysql.com/create-view.html
To create the view explicitly in a given database, use db_name.view_name syntax to qualify the view name with the database name: CREATE VIEW test.v AS SELECT * FROM t; Unqualified table or view names in the SELECT statement are also interpreted with ...If the view does not exist, CREATE OR REPLACE VIEW is the same as CREATE ...
https://dev.mysql.com/cursors.html
Cursors have these properties: Asensitive: The server may or may not make a copy of its result table Read only: Not updatable Nonscrollable: Can be traversed only in one direction and cannot skip rows Cursor declarations must appear before handler ...
https://dev.mysql.com/descending-indexes.html
MySQL supports descending indexes: DESC in an index definition is no longer ignored but causes storage of key values in descending order. Previously, indexes could be scanned in reverse order but at a performance penalty. A descending index can be ...
https://dev.mysql.com/explain.html
To give a hint to the optimizer to use a join order corresponding to the order in which the tables are named in a SELECT statement, begin the statement with SELECT STRAIGHT_JOIN rather than just SELECT. MySQL 8.0.18 introduces EXPLAIN ANALYZE, which ...In practice, the DESCRIBE keyword is more often used to obtain information about table structure, whereas EXPLAIN is used to obtain a query execution plan (that is, an explanation of how MySQL would execute a ...
https://dev.mysql.com/federated-create-connection.html
For example: CREATE TABLE federated_table ( id INT(20) NOT NULL AUTO_INCREMENT, name VARCHAR(32) NOT NULL DEFAULT '', other INT(20) NOT NULL DEFAULT '0', PRIMARY KEY (id), INDEX name (name), INDEX other_key (other) ) ENGINE=FEDERATED DEFAULT ... To ...
https://dev.mysql.com/federated-create-server.html
If you are creating a number of FEDERATED tables on the same server, or if you want to simplify the process of creating FEDERATED tables, you can use the CREATE SERVER statement to define the server connection parameters, just as you would with the ...
https://dev.mysql.com/federated-create.html
To create a FEDERATED table you should follow these steps: Create the table on the remote server. Alternatively, make a note of the table definition of an existing table, perhaps using the SHOW CREATE TABLE statement. Create the table on the local ...
https://dev.mysql.com/files-table.html
By comparison, INNODB_DATAFILES reports data from the InnoDB SYS_DATAFILES internal data dictionary table. This data is not available in the InnoDB SYS_DATAFILES internal data dictionary table, and is therefore not reported by INNODB_DATAFILES. The ...
Document created the 26/06/2006, last modified the 26/10/2018
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