/SQL/Left join vs inner join performance

Left join vs inner join performance

CREATE TABLE #Test1
(
    ID int NOT NULL PRIMARY KEY,
    Name varchar(50) NOT NULL
)
INSERT #Test1 (ID, Name) VALUES (1, 'One')
INSERT #Test1 (ID, Name) VALUES (2, 'Two')
INSERT #Test1 (ID, Name) VALUES (3, 'Three')
INSERT #Test1 (ID, Name) VALUES (4, 'Four')
INSERT #Test1 (ID, Name) VALUES (5, 'Five')

CREATE TABLE #Test2
(
    ID int NOT NULL PRIMARY KEY,
    Name varchar(50) NOT NULL
)
INSERT #Test2 (ID, Name) VALUES (1, 'One')
INSERT #Test2 (ID, Name) VALUES (2, 'Two')
INSERT #Test2 (ID, Name) VALUES (3, 'Three')
INSERT #Test2 (ID, Name) VALUES (4, 'Four')
INSERT #Test2 (ID, Name) VALUES (5, 'Five')

SELECT *
FROM #Test1 t1
INNER JOIN #Test2 t2
ON t2.Name = t1.Name

SELECT *
FROM #Test1 t1
LEFT JOIN #Test2 t2
ON t2.Name = t1.Name

DROP TABLE #Test1
DROP TABLE #Test2

Source: stackoverflow.com

Similar codes

1 vote192 views1 answer
Find a column in all tables postgres
SQL
4 votes188 views1 answer
Group by mysql and concatenate string
SQL
0 vote179 views1 answer
Sqldf change user
SQL
3 votes270 views1 answer
How to get yesterday date in sql
SQL
1 vote186 views1 answer
Oracle list constraints
SQL
3 votes241 views2 answers
Find string in stored procedure sql server
SQL
7 votes186 views2 answers
What is sql clause
SQL
0 vote202 views1 answer
Oracle pl/sql check if file exists
SQL
0 vote178 views1 answer
What is the difference between now() and current_date()?
SQL
1 vote191 views1 answer
Failed to stop mysqld.service: Unit mysqld.service not loaded.
SQL