This winter holiday season, give a precious gift to your career by upgrading your skills. | Get Flat 15 - 20% OFF on All Courses | Save Today

[iqquestion id=23]

6 thoughts on “Database : Database Operations Discussion 4

  • karim

    Joins are used to combine rows from two or more tables.
    Different joins are:
    1- Inner join.
    2- Left join.
    3- Right join.
    4- Full join.

  • nasir

    Join is a cross product of one or more tables. Allows us to combine information from two tables.
    Natural Join – that creates an implicit join clause based on the common columns in the two tables being joined. Common columns are columns that have the same name in both tables. It links two tables by selecting only rows with common values in their join columns and it’s a three steps process.
    Equi Join – Links tables on the basis of an equality condition that compares specified columns of each table. Outcome does not eliminate duplicate columns. In other words, the result will show the join column more than once.
    Theta Join – While joining the tables using join condition having any other comparison operator other than equal to (=), the join is called theta join.
    Right Outer Join – In normal join operations, the outcome shows only the rows of the tables having matching values in the join columns while the rows having unmatched values are discarded. While taking outer join between two tables A and B; If the result shows all the matching rows and the unmatched rows of A with the null values in the columns of B, the join is called Left Outer Join (allows the unmatched rows of left table to come).
    Left Outer Join – In normal join operations, the outcome shows only the rows of the tables having matching values in the join columns while the rows having unmatched values are discarded. While taking inner join between two tables A and B; If the result shows all the matching rows and the unmatched rows of B with the null values in the columns of A, the join is called Right Outer Join (allows the unmatched rows of right table to come).

  • Palwinder

    Join is a query which retrieves related columns or rows from multiple tables.Self Join – Joining the table with itself.Equi Join – Joining two tables …

  • collins

    join is when you want to joint multiply tables
    and the differnt type of joins are
    inner join
    outer join
    left join
    right joint

  • Olubunmi Ogunsola

    Join allows you to “join” more than one table together. Types of joins are inner, outer, left, and right.
    – Tomiwa

  • sivi ramesh

    SQL JOIN clause is used to combine rows from two or more tables, based on a common field between them.
    INNER JOIN: Returns all rows when there is at least one match in BOTH tables
    LEFT JOIN: Return all rows from the left table, and the matched rows from the right table
    RIGHT JOIN: Return all rows from the right table, and the matched rows from the left table
    FULL JOIN: Return all rows when there is a match in ONE of the tables

Leave a Reply