How do you set a variable in a SELECT statement in SQL Server?
To assign a value to a variable, use the SET statement. This is the preferred method of assigning a value to a variable. A variable can also have a value assigned by being referenced in the select list of a SELECT statement.
How do you set a variable in a SELECT statement?
The syntax for assigning a value to a SQL variable within a SELECT query is @ var_name := value , where var_name is the variable name and value is a value that you’re retrieving. The variable may be used in subsequent queries wherever an expression is allowed, such as in a WHERE clause or in an INSERT statement.
Can we use set with SELECT in SQL?
SET is used to assign a value to a variable and SELECT is used to assign a value or to select value from a variable/table/view etc. Let’s see the usage of SET and SELECT in different scenarios. In the above query both SET and SELECT are used to assign a value to a variable.
What are SQL Server variables?
A variable is an object that holds a single value of a specific type e.g., integer, date, or varying character string. We typically use variables in the following cases: As a loop counter to count the number of times a loop is performed. To hold a value to be tested by a control-of-flow statement such as WHILE .
Why set is used in SQL?
The SET command is used with UPDATE to specify which columns and values that should be updated in a table.
What is select distinct in SQL?
The SELECT DISTINCT statement is used to return only distinct (different) values. Inside a table, a column often contains many duplicate values; and sometimes you only want to list the different (distinct) values.
How do I select one column as distinct?
Adding the DISTINCT keyword to a SELECT query causes it to return only unique values for the specified column list so that duplicate rows are removed from the result set.
How do I set a variable in SQL?
Variables in SQL Data Warehouse are set using the DECLARE statement or the SET statement. Initializing variables with DECLARE is one of the most flexible ways to set a variable value in SQL Data Warehouse. DECLARE @v int = 0 ; You can also use DECLARE to set more than one variable at a time.
How do you declare variables in SQL?
Variables in SQL procedures are defined by using the DECLARE statement. Values can be assigned to variables using the SET statement or the SELECT INTO statement or as a default value when the variable is declared. Literals, expressions, the result of a query, and special register values can be assigned to variables.
What is a local variable in SQL?
Syntax. — Syntax for SQL Server and Azure SQL Database DECLARE { {@local_variable[AS]data_type[= value]}|{@cursor_variable_name CURSOR } }[,…n]|{
What are SQL variables?
A variable in SQL is an object that can hold a single data value of a specific type. In contrast, a parameter in SQL is an object that can exchange data between stored procedures and functions. These definitions explain the fundamental difference between variable and parameter in SQL.