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

The outer left join will be responsible for matching the record between the different rows of the left table. It will also return all of the rows from the left table. With this said, the outer right join will be responsible for matching the record between the different rows that can be seen on the right. It will also return all of the right tables.

The left join is going to have a different job from the right join. It will be responsible for joining the tables but it will always start at the leftmost table. The matched records from the first table to the second table will be noted. Take note that the left join and the left outer join are normally considered the same.

Joins are basically used in SQL so as to be able to make comparisons between several different sets of data. There are inner joins and outer joins. The inner join can only produce just one set of records, which is inside two tables, which are in comparison. The outer join brings about the full set of records which is present in the two tables which are being observed. The clause which produces distinct records after using a full join is the ‘where’ clause. The left and right elements of the table are connected by the Cartesian join. There is a major noticeable difference between left join and left outer join when used in the Microsoft SQL office server. In all, the use of the left join statement refers to the same statement. However, the use of the left outer join is instead recommended. The left outer join contains a full set of records, while the left join doesn’t.

To avoid confusion, left join and left outer join are terms that you will hear when referring to the SQL server. When you are typing it down, the word “outer” will be considered optional. They would be placed in square brackets. If you would leave them out, it will make a big difference with what you are trying to achieve. Outer Join will be allowed for ANSI 92 compatibility but left join cannot be used for this same purpose. The left outer join will also make sure that the data will be fetched properly in the left table. If you say left join, there are only selected items that you would need to fetch from the left table.

What do left join and outer left join mean? This is something that you need to know so that you can understand what these things will be used for. When you use the word “join” for SQL, this stands for the combination of different records that are in separate data. When you say outer join, this is a type of data that you will still be able to divide into two. The two parts will be called right join and left join. If you would try to look at a major difference between left join and outer left joint, you may not see much. They will just help you match data that you may not be able to see has similarities in the beginning.

Before delving into whether there is any difference between left join and left outer join, it is important that you know what the word 'join' means as far as the SQL server is concerned. Join is a feature that helps to combine certain records of two separate data.

Outer join is a type of this join and can be further divided into two i.e., right and left outer join. There is no big difference between the left join and left outer join since the latter is usually considered as another way of referring to the former. In terms of their functionalities, there is still no difference between the two since both are very similar in functions. Both the left join and the left outer join work by producing both matched and unmatched records that makeup two separate tables. Although both left join and left outer join are essentially the same, most people still prefer using left outer join to left join because it is more readable compared to left join.