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mariadb/storage/federated
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Monty f36ca142f7 Added page_range to records_in_range() to improve range statistics 
Prototype change:
-  virtual ha_rows records_in_range(uint inx, key_range *min_key,
-                                   key_range *max_key)
+  virtual ha_rows records_in_range(uint inx, const key_range *min_key,
+                                   const key_range *max_key,
+                                   page_range *res)

The handler can ignore the page_range parameter. In the case the handler
updates the parameter, the optimizer can deduce the following:
- If previous range's last key is on the same block as next range's first
  key
- If the current key range is in one block
- We can also assume that the first and last block read are cached!
  This can be used for a better calculation of IO seeks when we
  estimate the cost of a range index scan.

The parameter is fully implemented for MyISAM, Aria and InnoDB.
A separate patch will update handler::multi_range_read_info_const() to
take the benefits of this change and also remove the double
records_in_range() calls that are not anymore needed.
2020-03-27 03:54:45 +02:00
..
CMakeLists.txt Merge branch '5.5' into 10.1 2019-05-11 22:19:05 +03:00
ha_federated.cc Added page_range to records_in_range() to improve range statistics 2020-03-27 03:54:45 +02:00
ha_federated.h Added page_range to records_in_range() to improve range statistics 2020-03-27 03:54:45 +02:00
README

README 

The files in this directory are not used by MariaDB

MariaDB uses the new federated storage engine that can be found in the
federatedx directory.

This directory is only kept around to make it easy to merge code from the
MySQL source repositories that uses the old and disabled federated code.