Left Outer joins are useful in querying data from two tables and output is produced when based on Join condition mentioned in the where clause of the query. In the output, the rows that satisfy the join condition and all the remaining rows from the left side table will be fetched even if they do …
Inner joins are useful in querying data from two tables and output is produced when based on Join condition mentioned in the where clause of the query. In the output, only the rows that satisfy the join condition will be fetched. As the condition used in Inner join is based on equality of two columns …
Views in SQL is nothing but an SQL statement which is stored in the database and has an associated name. A View may hold all the rows in the table or some selected rows of the table. Also, a View may be created from one or more tables and depends on the query used Advantages …
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Triggers are a series of PL/SQL statements attached to a database table that executes whenever a triggering event (select, update, insert, delete) occurs. Unlike stored procedures and functions, they not explicitly called, but they are activated when a triggering event occurs. A trigger is nothing but a PL/SQL code executed automatically in response to a …
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Joins are useful in querying data from two or more tables. Joins are used to fetch the data from two tables based on some specific condition.There are following types of Joins: Equijoin Non-equijoin Outer join Self join Syntax for Join: Select table1.column, table2.column from table1, table2 where table1.column1 = table2.column2; Here, where clause is …
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