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https://dev.mysql.com/doc/refman/8.4/en/csv-storage-engine.html
When you create a CSV table, the server creates a plain text data file having a name that begins with the table name and has a .CSV extension. When you store data into the table, the storage engine saves it into the data file in comma-separated ...
https://dev.mysql.com/doc/refman/8.4/en/loading-tables.html
You could create a text file pet.txt containing one record per line, with values separated by tabs, and given in the order in which the columns were listed in the CREATE TABLE statement. In its simplest form, you supply values for each column, in ...
https://dev.mysql.com/doc/refman/8.4/en/show-profile.html
Note The SHOW PROFILE and SHOW PROFILES statements are deprecated; expect them to be removed in a future MySQL release. Use the Performance Schema instead; see Section 29.19.1, “Query Profiling Using Performance Schema”. To control profiling, ...
https://dev.mysql.com/doc/refman/8.4/en/windows-installation.html
Do not forget to use MAX_ROWS and AVG_ROW_LENGTH when you create tables. Note MySQL 8.4 Server requires the Microsoft Visual C++ 2019 Redistributable Package to run on Windows platforms. All of the files are located within this parent directory ...
https://dev.mysql.com/doc/internals/en/creating-handlerton.html
This is the name that will be used when creating tables (CREATE TABLE ... Possible values are defined in sql/handler.h and copied here: #define HTON_NO_FLAGS 0 #define HTON_CLOSE_CURSORS_AT_COMMIT (1 << 0) #define HTON_ALTER_NOT_SUPPORTED (1 << 1) ... The handlerton (short for handler singleton) defines the storage engine and contains method pointers to those methods that apply to the storage engine as a whole, as opposed to methods that work on a per-table ...
https://dev.mysql.com/doc/refman/8.4/en/precision-math-examples.html
Consider these statements: mysql> CREATE TABLE t (i INT, d DECIMAL, f FLOAT); mysql> INSERT INTO t VALUES(1,1,1); mysql> CREATE TABLE y SELECT AVG(i), AVG(d), AVG(f) FROM t; The result is a double only for the floating-point argument. This section ...
https://dev.mysql.com/doc/refman/8.4/en/select-optimization.html
Besides SELECT statements, the tuning techniques for queries also apply to constructs such as CREATE TABLE...AS SELECT, INSERT INTO...SELECT, and WHERE clauses in DELETE statements. Indexes are especially important for queries that reference ...
https://dev.mysql.com/doc/refman/8.4/en/constraint-foreign-key.html
MySQL supports ON UPDATE and ON DELETE foreign key references in CREATE TABLE and ALTER TABLE statements. MySQL requires that foreign key columns be indexed; if you create a table with a foreign key constraint but no index on a given column, an ...
https://dev.mysql.com/doc/refman/8.4/en/limit-optimization.html
MySQL sometimes optimizes a query that has a LIMIT row_count clause and no HAVING clause: If you select only a few rows with LIMIT, MySQL uses indexes in some cases when normally it would prefer to do a full table scan. If the server uses temporary ... 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 ...
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 ...