This will give you the same exact result as the previous example:Ī NATURAL JOIN is similar to a JOIN…USING, the difference is that it automatically tests for equality between the values of every column that exists in both tables.You can use this syntax whenever the two columns you are comparing are with the same name.SQLite infers the join condition automatically and compares the DepartmentId from both the tables – Students and Departments.Unlike the previous example, we didn’t write “ ON Students.DepartmentId = Departments.DepartmentId“.INNER JOIN Departments USING(DepartmentId) Explanation With “JOIN … USING” you don’t write a join condition, you just write the join column which is in common between the two joined table, instead of writing table1 “INNER JOIN table2 ON la = la” we write it like “table1 JOIN table2 USING(cola)”. The Difference between the INNER JOIN and JOIN. In such cases, there is no need to repeat them using the on condition and just state the column names and SQLite will detect that. USING” whenever the columns you will compare in the join condition are the same name. The INNER JOIN can be written using the “USING” clause to avoid redundancy, so instead of writing “ON Students.DepartmentId = Departments.DepartmentId”, you can just write “USING(DepartmentID)”. Whereas the students “Jena” and “George” were not included, because they have a null department Id, which doesn’t match the departmentId column from the departments table. That’s why only 8 students from 10 students were returned from this query with IT, math, and physics departments.The unmatched rows will be ignored and not included in the result. The INNER JOIN produces the records from both – the students and the department’s tables that match the condition which is “ S tudents.DepartmentId = Departments.DepartmentId “.The INNER word is optional, you can just write JOIN.Aliases can be specified for referenced tables.Then the join condition is specified with ON.The INNER JOIN clause is written after the first table referenced with “From” clause.
In the Select clause, you can select whatever columns you want to select from the two referenced tables.INNER JOIN Departments ON Students.DepartmentId = Departments.DepartmentId Explanation of code: In the following example, we will join the two tables “ Students” and “ Departments” with DepartmentId to get the department name for each student, as follows: SELECT The INNER JOIN returns only the rows that match the join condition and eliminate all other rows that don’t match the join condition. Now you are ready to run any type of query on the database. Step 2) Open the database “ TutorialsSampleDB.db” by the following command: Open My Computer and navigate to the following directory “ C:\sqlite” and.Note that, for all the following SQLite JOIN tables examples, you have to run the sqlite3.exe and open a connection to the sample database as flowing: JOIN-constraint – after you specified the tables or subqueries to join, you need to specify a join constraint, which will be a condition on which the matching rows that match that condition will be selected depending on the join type.JOIN operator – specify the join type (either INNER JOIN, LEFT OUTER JOIN, or CROSS JOIN).A table or a subquery which is the left table the table or the subquery before the join clause (on the left of it).
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