Top "Left-join" questions

Left JOIN faster or Inner Join faster?

So... which one is faster (NULl value is not an issue), and are indexed. SELECT * FROM A JOIN B b …

mysql left-join inner-join performance

what is the difference between left join and left outer join?

I have created 2 tables as CREATE TABLE table1(customerName VARCHAR(20),custid NUMBER ,order_id NUMBER ,price NUMBER ); CREATE TABLE table2(…

sql oracle join left-join outer-join

dplyr left_join by less than, greater than condition

This question is somewhat related to issues Efficiently merging two data frames on a non-trivial criteria and Checking if date …

sql r postgresql left-join dplyr

Doctrine 2 ManyToOne with multiple joinColumns

I'm trying to select the matching row in the product_item_sortorder table based on a productId and toolboxItemId from …

mapping left-join doctrine-orm many-to-one

Mysql Left Join Null Result

I have this query SELECT articles.*, users.username AS `user` FROM `articles` LEFT JOIN `users` ON articles.user_id = users.…

sql mysql null left-join

Postgres returns [null] instead of [] for array_agg of join table

I'm selecting some objects and their tags in Postgres. The schema is fairly simple, three tables: objects id taggings id | …

postgresql left-join database-normalization

Explain JOIN vs. LEFT JOIN and WHERE condition performance suggestion in more detail

In this candidate answer it is asserted that JOIN is better than LEFT JOIN under some circumstances involving some WHERE …

sql postgresql join left-join where

How can we differ LEFT OUTER JOIN vs Left Join

What is the difference between Left Join and Left Outer Join?

mysql join left-join outer-join

SQL Query to Join Two Tables Based Off Closest Timestamp

I have two tables in SQL and I need to be able to do a join based off of the …

sql timestamp left-join

SQL Server : left join results in fewer rows than in left table

I am using SQL Server (I believe it is 2005). I have TableA that has 2 columns and 439 rows (each row is …

sql sql-server left-join