mariadb/mysql-test/t/index_intersect.test

--disable_warnings
DROP TABLE IF EXISTS t1,t2,t3,t4;
DROP DATABASE IF EXISTS world;
--enable_warnings

set names utf8;

CREATE DATABASE world;

use world;

--source include/world_schema.inc

--disable_query_log
--disable_result_log
--disable_warnings
--source include/world.inc
--enable_warnings
--enable_result_log
--enable_query_log

SELECT COUNT(*) FROM Country;
SELECT COUNT(*) FROM City;
SELECT COUNT(*) FROM CountryLanguage;

CREATE INDEX Name ON City(Name);

--disable_query_log
--disable_result_log
--disable_warnings
ANALYZE TABLE City;
--enable_warnings
--enable_result_log
--enable_query_log


SET SESSION optimizer_switch='index_merge_sort_intersection=on';

SELECT COUNT(*) FROM City;

# The output of the next 6 queries tells us about selectivities
# of the conditions utilized in 4 queries following after them  

SELECT COUNT(*) FROM City WHERE Name LIKE 'C%';
SELECT COUNT(*) FROM City WHERE Name LIKE 'M%';
SELECT COUNT(*) FROM City WHERE Population > 1000000;
SELECT COUNT(*) FROM City WHERE Population > 500000;
SELECT COUNT(*) FROM City WHERE Population > 300000;
SELECT COUNT(*) FROM City WHERE Population > 5000000;

# The pattern of the WHERE condition used in the following 4 queries is
#   range(key1) AND range(key2)
# Varying values of the constants in the  conjuncts of the condition
# we can get either an index intersection retrieval over key1 and key2
# or a range index scan for one of these indexes

EXPLAIN
SELECT * FROM City WHERE
  Name LIKE 'C%' AND Population > 1000000; 

EXPLAIN
SELECT * FROM City WHERE
  Name LIKE 'M%' AND Population > 500000; 

EXPLAIN
SELECT * FROM City 
  WHERE Name LIKE 'M%' AND Population > 300000;

EXPLAIN
SELECT * FROM City
  WHERE Name LIKE 'M%' AND Population > 5000000;


# The following 8 queries check that 
# the previous 4 plans are valid and return
# the correct results when executed


SELECT * FROM City USE INDEX ()
  WHERE Name LIKE 'C%' AND Population > 1000000;
 
SELECT * FROM City
  WHERE Name LIKE 'C%' AND Population > 1000000; 


SELECT * FROM City USE INDEX ()
  WHERE Name LIKE 'M%' AND Population > 500000; 

SELECT * FROM City 
  WHERE Name LIKE 'M%' AND Population > 500000; 


SELECT * FROM City USE INDEX ()
  WHERE Name LIKE 'M%' AND Population > 300000;

SELECT * FROM City 
  WHERE Name LIKE 'M%' AND Population > 300000;


SELECT * FROM City USE INDEX ()
  WHERE Name LIKE 'M%' AND Population > 5000000;

SELECT * FROM City
  WHERE Name LIKE 'M%' AND Population > 5000000;


# The output of the next 7 queries tells us about selectivities
# of the conditions utilized in 3 queries following after them  

SELECT COUNT(*) FROM City WHERE Name BETWEEN 'M' AND 'N';
SELECT COUNT(*) FROM City WHERE Name BETWEEN 'G' AND 'J'; 
SELECT COUNT(*) FROM City WHERE Population > 1000000;
SELECT COUNT(*) FROM City WHERE Population > 700000;
SELECT COUNT(*) FROM City WHERE Population > 500000;
SELECT COUNT(*) FROM City WHERE Country LIKE 'C%';
SELECT COUNT(*) FROM City WHERE Country LIKE 'L%';


# The pattern of the WHERE condition used in the following 3 queries is
#   range(key1) AND range(key2) AND range(key3)
# Varying values of the constants in the  conjuncts of the condition
# we can get index intersection over different pairs of keys:
# over(key1,key2), over(key1,key3) and over(key2,key3)


EXPLAIN
SELECT * FROM City
  WHERE Name BETWEEN 'M' AND 'N' AND Population > 1000000 AND Country LIKE 'C%';

EXPLAIN
SELECT * FROM City 
  WHERE Name BETWEEN 'G' AND 'J' AND Population > 700000 AND Country LIKE 'L%';

EXPLAIN
SELECT * FROM City 
  WHERE Name BETWEEN 'G' AND 'J' AND Population > 500000 AND Country LIKE 'C%';


# The following 6 queries check that 
# the previous 3 plans are valid and return
# the correct results when executed


SELECT * FROM City USE INDEX ()
  WHERE Name BETWEEN 'M' AND 'N' AND Population > 1000000 AND Country LIKE 'C%';

SELECT * FROM City
  WHERE Name BETWEEN 'M' AND 'N' AND Population > 1000000 AND Country LIKE 'C%';


SELECT * FROM City USE INDEX ()
  WHERE Name BETWEEN 'G' AND 'J' AND Population > 700000 AND Country LIKE 'M%';

SELECT * FROM City 
  WHERE Name BETWEEN 'G' AND 'J' AND Population > 700000 AND Country LIKE 'M%';


SELECT * FROM City USE INDEX ()
  WHERE Name BETWEEN 'G' AND 'J' AND Population > 500000 AND Country LIKE 'C%';

SELECT * FROM City 
  WHERE Name BETWEEN 'G' AND 'J' AND Population > 500000 AND Country LIKE 'C%';


# The output of the next 9 queries tells us about selectivities
# of the conditions utilized in 5 queries following after them  

SELECT COUNT(*) FROM City WHERE ID BETWEEN 500 AND 999;
SELECT COUNT(*) FROM City WHERE ID BETWEEN 3500 AND 3999;
SELECT COUNT(*) FROM City WHERE ID BETWEEN 1 AND 1000;
SELECT COUNT(*) FROM City WHERE Population > 700000;
SELECT COUNT(*) FROM City WHERE Population > 1000000;
SELECT COUNT(*) FROM City WHERE Population > 300000;
SELECT COUNT(*) FROM City WHERE Country LIKE 'C%';
SELECT COUNT(*) FROM City WHERE Country LIKE 'A%';
SELECT COUNT(*) FROM City WHERE Country BETWEEN 'S' AND 'Z';


# The pattern of the WHERE condition used in the following 5 queries is
#   range(key1) AND range(key2) AND range(key3)
# with key1 happens to be a primary key (it matters only for InnoDB)
# Varying values of the constants in the  conjuncts of the condition
# we can get index intersection  either over all three keys, or over
# different pairs, or a range sacn over one of these keys.
# Bear in mind that the condition (Country LIKE 'A%') is actually
# equivalent to the condition (Country BETWEEN 'A' AND 'B') for the
# tested instance the table City. 


EXPLAIN
SELECT * FROM City
  WHERE ID BETWEEN 500 AND 999 AND Population > 700000 AND Country LIKE 'C%';

EXPLAIN
SELECT * FROM City
  WHERE ID BETWEEN 500 AND 999 AND Population > 1000000 AND Country LIKE 'A%';

EXPLAIN
SELECT * FROM City 
  WHERE ID BETWEEN 500 AND 999 AND Population > 300000 AND Country LIKE 'C%';

EXPLAIN
SELECT * FROM City 
  WHERE ID BETWEEN 3500 AND 3999 AND Population > 700000
        AND Country BETWEEN 'S' AND 'Z';

EXPLAIN
SELECT * FROM City 
  WHERE ID BETWEEN 1 AND 1000 AND Population > 700000
        AND Country BETWEEN 'S' AND 'Z' ;


# The following 10 queries check that 
# the previous 5 plans are valid and return
# the correct results when executed


SELECT * FROM City USE INDEX ()
  WHERE ID BETWEEN 500 AND 999 AND Population > 700000 AND Country LIKE 'C%';

SELECT * FROM City
  WHERE ID BETWEEN 500 AND 999 AND Population > 700000 AND Country LIKE 'C%';


SELECT * FROM City USE INDEX ()
  WHERE ID BETWEEN 500 AND 999 AND Population > 1000000 AND Country LIKE 'A%';

SELECT * FROM City
  WHERE ID BETWEEN 500 AND 999 AND Population > 1000000 AND Country LIKE 'A%';


SELECT * FROM City USE INDEX ()
  WHERE ID BETWEEN 500 AND 999 AND Population > 300000 AND Country LIKE 'C%';

SELECT * FROM City 
  WHERE ID BETWEEN 500 AND 999 AND Population > 300000 AND Country LIKE 'C%';


SELECT * FROM City USE INDEX ()
  WHERE ID BETWEEN 3500 AND 3999 AND Population > 700000
        AND Country BETWEEN 'S' AND 'Z';

SELECT * FROM City 
  WHERE ID BETWEEN 3500 AND 3999 AND Population > 700000
        AND Country BETWEEN 'S' AND 'Z';


SELECT * FROM City USE INDEX ()
  WHERE ID BETWEEN 1 AND  1000 AND Population > 700000
        AND Country BETWEEN 'S' AND 'Z' ;

SELECT * FROM City 
  WHERE ID BETWEEN 1 AND  1000 AND Population > 700000
        AND Country BETWEEN 'S' AND 'Z' ;


SET SESSION sort_buffer_size = 2048;


# The following EXPLAIN command demonstrate that the execution plans
# may be different if sort_buffer_size is set to a small value


EXPLAIN
SELECT * FROM City WHERE
  Name LIKE 'C%' AND Population > 1000000; 

EXPLAIN
SELECT * FROM City WHERE
  Name LIKE 'M%' AND Population > 500000; 


EXPLAIN
SELECT * FROM City
  WHERE Name LIKE 'C%' AND Population > 1000000 AND Country LIKE 'C%';

EXPLAIN
SELECT * FROM City 
  WHERE  Name BETWEEN 'G' AND 'J' AND Population > 700000 AND Country LIKE 'M%';

EXPLAIN
SELECT * FROM City 
  WHERE  Name BETWEEN 'G' AND 'J' AND Population > 500000 AND Country LIKE 'C%';


EXPLAIN
SELECT * FROM City
  WHERE ID BETWEEN 500 AND 999 AND Population > 1000000 AND Country LIKE 'A%';

EXPLAIN
SELECT * FROM City 
  WHERE ID < 1000 AND Population > 700000 AND Country LIKE 'C%';


#Yet the query themselves return the correct results in this case as well


SELECT * FROM City WHERE
  Name LIKE 'C%' AND Population > 1000000; 

SELECT * FROM City WHERE
  Name LIKE 'M%' AND Population > 500000; 


SELECT * FROM City
  WHERE Name BETWEEN 'M' AND 'N' AND Population > 1000000 AND Country LIKE 'C%';

SELECT * FROM City 
  WHERE  Name BETWEEN 'G' AND 'J' AND Population > 700000 AND Country LIKE 'M%';

SELECT * FROM City 
  WHERE  Name BETWEEN 'G' AND 'J' AND Population > 500000 AND Country LIKE 'C%';


SELECT * FROM City
  WHERE ID BETWEEN 500 AND 999 AND Population > 1000000 AND Country LIKE 'A%';

SELECT * FROM City 
  WHERE ID < 1000 AND Population > 700000 AND Country LIKE 'C%';


SET SESSION sort_buffer_size = default;

# Instead of the index on the column Country create two compound indexes
# including this column as the first component

DROP INDEX Country ON City;

CREATE INDEX CountryID ON City(Country,ID);
CREATE INDEX CountryName ON City(Country,Name);

--disable_query_log
--disable_result_log
--disable_warnings
ANALYZE TABLE City;
--enable_warnings
--enable_result_log
--enable_query_log

# Check that the first component of a compound index can be used for
# index intersection, even in the cases when we have a ref access
# for this component

EXPLAIN
SELECT * FROM City 
  WHERE Country LIKE 'M%' AND Population > 700000;

EXPLAIN
SELECT * FROM City 
  WHERE Country='CHN' AND Population > 1000000;

EXPLAIN
SELECT * FROM City 
  WHERE Country='CHN' AND Population > 1000000 AND Name LIKE 'C%';


# Check that the previous 3 plans return the right results when executed


SELECT * FROM City USE INDEX ()
  WHERE Country LIKE 'M%' AND Population > 700000;

SELECT * FROM City 
  WHERE Country LIKE 'M%' AND Population > 700000;


SELECT * FROM City USE INDEX ()
  WHERE Country='CHN' AND Population > 1000000;

SELECT * FROM City 
  WHERE Country='CHN' AND Population > 1000000;


SELECT * FROM City USE INDEX ()
  WHERE Country='CHN' AND Population > 1000000 AND Name LIKE 'C%';

SELECT * FROM City 
  WHERE Country='CHN' AND Population > 1000000 AND Name LIKE 'C%';


DROP DATABASE world;

use test;

SET SESSION optimizer_switch='index_merge_sort_intersection=on';