Control of Flow StatementsĪllow you to use logic and looping constructs within your program. Reference the parameters directly within your code, or assign them to T-SQL variables. You’ll use parameters “to pass” values from a call procedure to the current. These are the statement you us to create the SPROC and it’s parameters. You’ll see their code or programming is categorized as: Definition Statements When writing stored procedures, remember most SP’s purpose is to run queries! Given this, SQL such as SELECT statements, make up a majority stored procedure’s code. Now that we have seen an example, let’s look to see what it takes to create one for ourselves. Each language, such as PHP or C#, has its specific methods for doing so. Stored procedures can also be called from within a programming language. To call it from the SQL server command line or from another one you would use the following: exec pFindEmployee 3 It possible to execute a stored procedure from within SQL Server. Though this example returns a single row, due to the fact we are matching to the primary key, keep in mind stored procedures can also return multiple rows, or a single (scalar) value. Specifically, it accepts the BusinessEntityID as a parameter and uses this to match the primary key of the HumanResources.Employee table to return the requested employee. Here is an example of a stored procedure that takes a parameter, executes a query, and returns a result. Also, as mentioned above, if configured for OUTPUT, parameters are able to propagate changed values back to the calling procedure. They can return a single value such as a number or text value or a result set (set of rows). This can slow down database performance, so be intelligent about your use of cursors! Outputs In essence you can use cursors to loop through a SQL statement’s result. Cursors allow the procedure to access results row by row. SPROCS can become very handy as they can manipulate results of SQL queries via cursors. SPROCS execute SQL statements, and use control of flow statements, such as IF THEN or CASE statements and lopping constructs to perform tasks.Ī stored procedure is able to call another. Depending on how you define the parameters, the proc passes modified values back to the calling program. Store procedure can accept parameter values as inputs. Traditionally Oracle uses PL/SQL as its language whereas, SQL Server uses T/SQL. Stored procedure features and command syntax are specific to the database engine. A stored procedure is a group of one or more database statements housed in the database’s data dictionary and called from either a remote program, another stored procedure, or the command line.
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