Usage of foreach in sql

The FOREACH statement in SQL is used to perform loop operations on multiple rows in a table, including traversing the rows in the table, performing operations for each row, and filtering rows based on conditions. The syntax is FOREACH (rowset_expression) AS FOR EACH ROW statement_list.

Usage of FOREACH in SQL

The FOREACH statement is used in SQL to execute a series of rows in a table Loop operation. It is mainly used in the following scenarios:

• Loop through multiple rows in the table
• Perform one or more operations on each row
• Filter rows based on conditions

Syntax:

<code>FOREACH (rowset_expression) AS FOR EACH ROW
  statement_list</code>

Where:

• rowset_expression Specifies the table or query results to be traversed
• statement_list Specify the SQL statement to be executed

Usage example:

The following example uses FOREACH to traverse Customers table and output the name and address for each customer:

<code class="sql">DECLARE @Customers TABLE (
  ID int,
  Name nvarchar(50),
  Address nvarchar(100)
);
INSERT INTO @Customers (ID, Name, Address) VALUES
  (1, 'John Doe', '123 Main Street'),
  (2, 'Jane Smith', '456 Oak Avenue');

FOREACH (row IN @Customers) AS FOR EACH ROW
  SELECT Name, Address FROM row;</code>

Note:

##FOREACH statement must be used within a BEGIN...END block .
• rowset_expression can be a table variable, table expression, or query.
• statement_list can contain any valid SQL statement, such as SELECT, INSERT, UPDATE, and DELETE.
• FOREACH statement can also be used to handle cursors.

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