Which of the following join returns the records that match the values for the join columns from both the tables on the join?
SQL Join statement is used to combine data or rows from two or more tables based on a common field between them. Different types of Joins are as follows: Show
Student StudentCourse The simplest Join is INNER JOIN. A. INNER JOINThe INNER JOIN keyword selects all rows from both the tables as long as the condition is satisfied. This keyword will create the result-set by combining all rows from both the tables where the condition satisfies i.e value of the common field will be the same. Syntax: SELECT table1.column1,table1.column2,table2.column1,.... FROM table1 INNER JOIN table2 ON table1.matching_column = table2.matching_column; table1: First table. table2: Second table matching_column: Column common to both the tables.
Example Queries(INNER JOIN) This query will show the names and age of students enrolled in different courses. SELECT StudentCourse.COURSE_ID, Student.NAME, Student.AGE FROM Student INNER JOIN StudentCourse ON Student.ROLL_NO = StudentCourse.ROLL_NO;Output: B. LEFT JOINThis join returns all the rows of the table on the left side of the join and matches rows for the table on the right side of the join. For the rows for which there is no matching row on the right side, the result-set will contain null. LEFT JOIN is also known as LEFT OUTER JOIN. Syntax: SELECT table1.column1,table1.column2,table2.column1,.... FROM table1 LEFT JOIN table2 ON table1.matching_column = table2.matching_column; table1: First table. table2: Second table matching_column: Column common to both the tables.
Example Queries(LEFT JOIN): SELECT Student.NAME,StudentCourse.COURSE_ID FROM Student LEFT JOIN StudentCourse ON StudentCourse.ROLL_NO = Student.ROLL_NO;Output: C. RIGHT JOINRIGHT JOIN is similar to LEFT JOIN. This join returns all the rows of the table on the right side of the join and matching rows for the table on the left side of the join. For the rows for which there is no matching row on the left side, the result-set will contain null. RIGHT JOIN is also known as RIGHT OUTER JOIN. Syntax: SELECT table1.column1,table1.column2,table2.column1,.... FROM table1 RIGHT JOIN table2 ON table1.matching_column = table2.matching_column; table1: First table. table2: Second table matching_column: Column common to both the tables.
Example Queries(RIGHT JOIN): SELECT Student.NAME,StudentCourse.COURSE_ID FROM Student RIGHT JOIN StudentCourse ON StudentCourse.ROLL_NO = Student.ROLL_NO;Output: D. FULL JOINFULL JOIN creates the result-set by combining results of both LEFT JOIN and RIGHT JOIN. The result-set will contain all the rows from both tables. For the rows for which there is no matching, the result-set will contain NULL values. Syntax: SELECT table1.column1,table1.column2,table2.column1,.... FROM table1 FULL JOIN table2 ON table1.matching_column = table2.matching_column; table1: First table. table2: Second table matching_column: Column common to both the tables.Example Queries(FULL JOIN): SELECT Student.NAME,StudentCourse.COURSE_ID FROM Student FULL JOIN StudentCourse ON StudentCourse.ROLL_NO = Student.ROLL_NO;Output:
Left JOIN (Video) This article is contributed by Harsh Agarwal. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to . See your article appearing on the GeeksforGeeks main page and help other Geeks. Please write comments if you find anything incorrect, or if you want to share more information about the topic discussed above. Which join returns rows when there is a match in both tables?INNER JOIN TABLE2
When the Join condition is met, it returns matched rows in both tables with the selected columns in the SELECT clause.
Which join returns records when the values match in the joining tables?An INNER JOIN is such type of join that returns all rows from both the participating tables where the key record of one table is equal to the key records of another table. This type of join required a comparison operator to match rows from the participating tables based on a common field or column of both the tables.
Which type of join is used to returns all records when there is a match in either left or right table?The FULL OUTER JOIN keyword returns all records when there is a match in left (table1) or right (table2) table records.
Which type of join returns rows from two table only if there is a match between column in both table?Outer joins are joins that return matched values and unmatched values from either or both tables. There are a few types of outer joins: LEFT JOIN returns only unmatched rows from the left table, as well as matched rows in both tables.
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