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https://dev.mysql.com/doc/internals/en/innodb-infimum-and-supremum-records.html
InnoDB sets up an infimum record and a supremum record automatically in the root page when an index is first created, and never deletes them. The infimum and supremum records can be considered part of the overhead of an index page. Initially, they ... “Infimum” and “Supremum” are mathematical terms that refer to the outer bounds of an ordered ...
https://dev.mysql.com/doc/internals/en/optimizer-partition-pruning.html
In both cases we have a WHERE clause as input: the range access method needs index ranges (that is, intervals) to scan; partition pruning module needs partitioning intervals so that it can determine which partitions should be used. For range access, ...Partitions that did not get into this set (that is, those that were pruned away) will not be accessed at all: this is how query execution is made ...
https://dev.mysql.com/doc/internals/en/optimizer-partition-selection.html
If a partitioned table is accessed in a series of index lookups (that is, using the ref, eq_ref, or ref_or_null access methods), MySQL checks to see whether it needs to make index lookups in all partitions or that it can limit access to a ...If ...
https://dev.mysql.com/doc/internals/en/optimizer-transpositions.html
Thus: WHERE 5 = -column1 is not treated the same as: WHERE column1 = -5 Transpositions to expressions of the form column = constant are ideal for index lookups. If an expression of this form refers to an indexed column, then MySQL always uses the ...
https://dev.mysql.com/doc/internals/en/select-special-engines.html
The normal engine can be replaced with such special engines only during the optimization process.
https://dev.mysql.com/doc/ndbapi/en/ndb-ndbrecord.html
You can also use NdbRecord in conjunction with the PartitionSpec structure to perform scans that take advantage of partition pruning, using NdbIndexScanOperation::setBound(). Decription NdbRecord is an interface which provides a mapping to a full or ...
https://dev.mysql.com/doc/ndbapi/en/ndb-table.html
Table::getColumn() Description This method is used to obtain a column definition, given either the index or the name of the column. Return value A pointer to the column with the specified index or name. This section provides information about the ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-config-metric-optimizer-category.html
Eq Range Index Dive Limit Indicates the number of equality ranges in an equality comparison condition when the optimizer switches from using index dives to index statistics in estimating the number of qualifying rows. Lists the Optimizer ...
https://dev.mysql.com/doc/x-devapi-userguide/en/fetching-all-data-items-at-once.html
In addition to the pattern of using fetchOne() explained at Section 9.3, “Working with Data Sets”, which enables applications to consume data items one by one, X DevAPI also provides a pattern using fetchAll(), which passes all data items of a ...
https://dev.mysql.com/doc/x-devapi-userguide-shell-js/en/fetching-all-data-items-at-once.html
execute(); var myRows = myResult.fetchAll(); for (index in myRows){ print (myRows[index].name + " is " + myRows[index].age + " years old."); } When mixing fetchOne() and fetchAll() to read from one data set keep in mind that every call to fetchOne() ... In addition to the pattern of using fetchOne() explained at Section 9.3, “Working with Data Sets”, which enables applications to consume data items one by one, X DevAPI also provides a pattern using fetchAll(), which passes all data items of a data set as a list to the ...