UNION operator makes it possible to connect 2 results of query and remove all existing duplicities in them. In other words, operator actually performs DISTINCT in final unification of records. Syntax SELECT Column FROM dbo.Table WHERE Condition UNION SELECT Column FROM dbo.Table WHERE Condition; Syntax is same as in all Set operators. Result… Read More »
IN operator in t-sql is used in cases where we need to specify a condition e.g in WHERE clause to multiple discrete values at once. It is similar to BETWEEN operator but there is one big difference. Difference between IN and BETWEEN: BETWEEN can be used to define range which is continuous IN is used… Read More »
This operator is used in SQL whenever it is needed to prove if certain value belongs to some range. This operator is used together with “AND” command which defines given range. Operator can be used in most of the clauses but is most common in WHERE for defining limiting requirement. Syntax SELECT [Date] FROM [dbo].[Table]… Read More »
EXISTS is a T-SQL operator which can be used to test existence of a result in subquery. Based on that it can perform query or some task. Sql EXISTS performs so called “Existence test”. Syntax 1) SQL Query SELECT Columns FROM dbo.Table WHERE EXISTS (SELECT columns FROM Dbo.Table2 WHERE Condition);… Read More »
This operator can find string of text based on a certain pattern. It is most usually used in clause WHERE. But it can be applied in any part of SQL query, for example in SELECT, UPDATE or DELETE. T-SQL LIKE has the following syntax: Syntax: SELECT <Column 1> FROM dbo.Table WHERE <Column 1> LIKE <patern>;… Read More »