Search Results
https://dev.mysql.com/doc/internals/en/myisam-column-attributes.html
When sending a key to the handler for index_read() or records_in_range, we always use a 2-byte length for the VARCHAR to make things simpler. Next I'll describe the physical attributes of each column in a row. The format depends entirely on the ...
https://dev.mysql.com/doc/internals/en/myisam-introduction.html
MySQL creates files named Table1.MYD ("MySQL Data"), Table1.MYI ("MySQL Index"), and Table1.frm ("Format"). These files will be in the directory: /<datadir>/<database>/ For example, if you use Linux, you might find the files in the ...
https://dev.mysql.com/doc/internals/en/mysql-services-for-plugins.html
For information about plugins for testing plugin services, see the Plugins for Testing Plugin Services section of the MySQL Server Doxygen documentation, available at https://dev.mysql.com/doc/index-other.html. As of MySQL 5.5, plugins have access ...
https://dev.mysql.com/doc/internals/en/optimizer-code.html
The make_join_statistics() routine puts together all the information it can find about indexes that might be useful for accessing the query's tables. This diagram shows the structure of the function handle_select() in /sql/sql_select.cc (the server ...
https://dev.mysql.com/doc/internals/en/optimizer-joins-access-methods.html
Bad join choices can cause more damage than bad choices in single-table searches, so MySQL developers have spent proportionally more time making sure that the tables in a query are joined in an optimal order and that optimal access methods (often ...
https://dev.mysql.com/doc/internals/en/optimizer-late-nulls-filtering.html
Before performing an index lookup, we determine whether any of the expri values is NULL. Suppose we have a query plan with table tblX being accessed via the ref access method: tblX.key_part1 = expr1 AND tblX.key_part2 = expr2 AND ... If it is, we ...
https://dev.mysql.com/doc/internals/en/records-in-range.html
Used by optimizer to calculate cost of using a particular index. Purpose For the given range how many records are estimated to be in this range. Synopsis virtual ha_rows records_in_range ( inx, min_key, max_key); uint inx ; key_range * min_key ; ...
https://dev.mysql.com/doc/internals/en/replication-not-guaranteed.html
(P-exception-federated) If a table uses a federated table on the master, then TODO (P-exception-table-definition) If a CREATE TABLE uses a DATA DIRECTORY or INDEX DIRECTORY clause, then the table may not be correctly replicated. There are some ...
https://dev.mysql.com/doc/internals/en/stored-programs.html
The content formerly located in this chapter is now maintained in the Stored Programs section of the MySQL Server Doxygen documentation, available at https://dev.mysql.com/doc/index-other.html.
https://dev.mysql.com/doc/ndbapi/en/mccj-clusterj-annotation-columns.html
This annotation is used for multi-column structures such as indexes and keys. 4.3.2.2.1 Synopsis @Target(value={java.lang.annotation.ElementType.FIELD, java.lang.annotation.ElementType.METHOD, java.lang.annotation.ElementType.TYPE}) ...