SQL Server set operators are used to compare multiple values of a column. These operators return TRUE or FALSE based on whether the values in the columns match any of the values in the set.
The LEFT OUTER JOIN operator performs a join between two tables based on matching values in the left table only. If there are no matches, NULL results are returned. The difference between LEFT OUTER and INNER JOIN is that LEFT OUTER will not return any rows from the right table if there are no matches. That’s why it’s called “left outer.” The INNER JOIN operator does not have this behavior because it will return all rows from both tables if there are no matches at all (if we don’t specify ON clause).
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Set Operators In SQL Server With Examples
SQL set operators are used to combine a group of values into a single value.
The set operators in SQL are UNION, INTERSECT and EXCEPT.
UNION operator is used to combine multiple query results into one result set.
INTERSECT operator is used to return only the rows that are common between two queries.
EXCEPT operator is used to return only the rows that are unique to a query but not present in another query.
The set operators in SQL are used to compare two sets of rows. The result of the comparison is a Boolean value TRUE or FALSE.
The following are the set operators:
UNION: The UNION operator returns all distinct rows from both tables.
INTERSECT: The INTERSECT operator returns all rows that are common to both tables.
MINUS: The MINUS operator returns all rows that are present in Table 1 but not in Table 2.
EXCEPT: The EXCEPT operator returns all rows that are present in Table 1 but not in Table 2.
SQL Set Operators
The set operators are used to compare two sets of values and return true or false. The result of the comparison is a single Boolean value that indicates whether or not the two sets are equal. There are three types of set operators: UNION, INTERSECT and EXCEPT.
Set operators work on two or more tables and return a result table containing all rows from each table in the FROM clause. If you want to use a set operator in your query, you must have at least two tables in your FROM clause.
UNION Operator
The UNION operator combines one or more SELECT statements into one query by combining their results together. The UNION operator returns only distinct values so duplicate values are eliminated before being returned. The UNION operator can be used with any number of SELECT statements as long as the columns selected have compatible datatypes (i.e., all numeric columns must be numeric). For example:
SELECT * FROM Table_1 UNION SELECT * FROM Table_2;
The set operators are used to perform set operations on two sets. In SQL Server, there are three types of set operators: UNION, EXCEPT and INTERSECT.
The UNION operator is used to combine two or more queries into a single result set.
The EXCEPT operator is used to return the rows from the first query that are not present in the second query.
The INTERSECT operator returns the rows that are common to both queries.
UNION Operator: The UNION operator combines two or more queries into a single result set. The UNION operator removes duplicate rows from its arguments and returns only one row for each group of duplicates. For example, if we have two tables named tbl_a and tbl_b with identical structure, then the following query will return only one row for each group of duplicates: SELECT * FROM tbl_a UNION SELECT * FROM tbl_b;
INNER JOIN
The INNER JOIN clause is used to link two or more tables based on a common column. The result set will have all rows from the first table that have a matching value in the second table.
Syntax:
SELECT * FROM table1 INNER JOIN table2 ON table1.column = table2.column;
Example:
SELECT * FROM customer INNER JOIN orders ON customer.cust_id = orders.cust_id;
OUTER JOIN
The OUTER JOIN clause is used to link two or more tables based on a common column. The result set will have all rows from the first table that have a matching value in the second table, as well as matching rows from the second table that do not have an equivalent match in the first one. For example, suppose we want to find out all customers who had not placed any orders in the last six months and still remain active customers of our company? Using OUTER JOIN clause we can easily get those customers who are active but haven’t placed any orders:
SELECT * FROM customer OUTER JOIN orders ON customer.cust_id = orders.cust_id AND orders.[date] > ’01
SQL Set Operators
The SQL set operators are used to compare two sets of data and return a Boolean value. The result of the comparison is either TRUE or FALSE.
In this article, we will see how to use these set operators in Oracle.
The following table lists the set operators that can be used in Oracle:
Operator Description Example = Equality operator Returns TRUE if both operands are equal, otherwise returns FALSE. [A] = [B] != Inequality operator Returns TRUE if both operands are not equal, otherwise returns FALSE. [A] != [B] <> Inequality operator Returns TRUE if both operands are not equal, otherwise returns FALSE. [A] <> [B] LIKE Operator Applies LIKE conditions on string values, which allows you to find values that match a pattern or contain wildcards characters such as a question mark (?). [A] LIKE [B] NOT IN Operator Checks whether an element is not a member of a set; returns TRUE if it is not part of the set and FALSE otherwise. The expression x NOT IN y evaluates to TRUE if x does not exist among the rows of y
The set operators are used to compare sets of values. The following table lists the set operators that can be used in SQL.
Operator Symbol Description
in ( )Returns true if the specified column is a member of the specified set.
not in ( )Returns true if the specified column is not a member of the specified set.
like ( )Returns true if the comparison between two values matches any part of either value, as defined by the _pattern_ placeholder in LIKE comparisons.
greater than ( > )Returns true if the first operand is greater than the second operand.
greater than or equal to ( >= )Returns true if the first operand is greater than or equal to the second operand.
less than ( < )Returns true if the first operand is less than the second operand.
less than or equal to ( <= )Returns true if the first operand is less than or equal to the second operand
The set operators are used to perform operations on sets of data. The set operator selects a subset of data from the input dataset.
The following are the set operators:
UNION: The UNION operator is used to combine two or more queries into one query.
INTERSECT: The INTERSECT operator gets all records that are common between two or more queries.
EXCEPT: The EXCEPT operator gets all records that are unique to one query, but not in another query.
Set operators are used to combine two or more sets into a single set.
The following table lists the set operators supported by Oracle.
Name Description Example
UNION Returns the result of combining two or more tables or queries with identical row and column names. SELECT * FROM t1 UNION SELECT * FROM t2;
INTERSECT Returns the result of combining two or more tables or queries that have matching rows only. SELECT * FROM t1 INTERSECT SELECT * FROM t2;
EXCEPT Returns the result of combining two or more tables or queries that have matching rows only but not matching columns. SELECT * FROM t1 EXCEPT SELECT * FROM t2;
The set operators in Oracle are:
UNION
INTERSECT
MINUS
EXCEPT https://www.youtube.com/watch?v=G2C3bH0qFNU
UNION ALL
The UNION operator returns all the rows that are common to both the operands. The rows that are unique to either of the operands are not included in the result set. The INTERSECT operator returns all rows that have common values for specified columns between two queries. The MINUS operator returns all rows that are present in one query but not in another query. The EXCEPT operator returns all rows that are present in one query but not present in another query. The UNION ALL operator returns all rows from both queries, including duplicates.