![]() ![]() So they recommend “a good understanding of how these structures are created and how are they used”. “For them, the importance of knowing about databases and their operation lies in the fact that “practically all modern systems rely on them (databases)”. In short they note that databases “are specialized structures that allow computerized systems to store, handle, and retrieve data very quickly” in their book “Databases: Design, Implementation, and Administration. However, in view of specialists Carlos Coronel, Steven Morris, and Peter Rob, this explanation might be a little inadequate. Furthermore, They resemble a sizable library, but rather than having actual books, documents, or magazines, the data is digitally recorded and kept on discs that enable access to it from any location in the world. To begin with, the first thing to understand is that databases are collections of related information that are arranged and stored in a specific way. Knowing how to manage and use this data becomes a competitive advantage. This phrase from the philosopher Francis Bacon becomes relevant in an increasingly globalized and digitized world, where databases have become repositories of raw information that anyone can access. So, the SQL query built using this method is always the same regardless of how it gets called or the user input supplied at run time.“Information is power”. The difference between EXEC and sp_executesql is that the former treats the string parameter as an SQL statement while the latter is a system procedure whose first parameter is a parameterized SQL statement and the second parameter is a parameter-list declaration, similar to the parameter list present in the declaration of a stored procedure and all that remains are simply the parameters in that parameter-list. In addition, sp_executesql is being used to execute with the parameter list and the parameterized SQL statements. It is rather being passed as parameter to the SQL statement. This way, the user input is not enclosed inside the single quotes. SELECT = ' SELECT EmployeeMiddleName, EmployeeSurname, SSN ' + ' FROM HumanResources.Employee ' + ' WHERE ' IF IS NOT NULL SELECT = + ' employeeName LIKE ''' + + '''' END GO - Modified source: Click the Execute button to create new stored procedureįor instance, the unsafe stored procedure that was considered at the beginning of the article will be encapsulated as:.Click the Create script button to open generated script in the Query editor.Click the Preview button to preview how the code will be modified:.In the Name field type a new name of the stored procedure and specify its schema using the Schema drop-down menu.Select the Encapsulate code as -> Stored procedure command In the ApexSQL menu, select ApexSQL Refactor.Select the body of the stored procedure.Open the stored procedure for editing in either SQL Server Management Studio or Visual Studio.To secure stored procedures from SQL injection attacks: It expands wildcards, fully qualifies object names, renames SQL database objects and parameters without breaking dependencies and much more. The fastest way to ensure all stored procedures are safe from SQL injection is to use ApexSQL Refactor.ĪpexSQL Refactor is a SQL Server Management Studio and Visual Studio add-in which formats and refactors SQL code using 11 code refactors and over 200 formatting options. Which will result in returning all the rows from the table, as well as executing the Windows command DIR. WHERE employeeName LIKE '1' OR '1' = '1' EXEC master. SELECT EmployeeMiddleName, EmployeeSurname, SSN Instead of the parameter being a search string to the SQL query, the user input has become the part of the query itself as it is enclosed inside the single quotes. The reason for this is that the user input is enclosed in the single quotes and concatenated to a string to form a SQL query. Therefore, the above stored procedure is still vulnerable to SQL injection even though the user inputs are passed to it as parameters. SELECT = ' SELECT EmployeeMiddleName, EmployeeSurname, SSN ' + ' FROM HumanResources.Employee ' + ' WHERE ' IF IS NOT NULL SELECT = + ' employeeName LIKE ''' + + '''' EXEC value for the variable is directly taken from whatever the user inputs and concatenated with the contents of the variable In addition, the EXEC command, which takes a string as a parameter and executes it as a SQL statement, is being used. CREATE PROCEDURE usp_GetEmployee varchar(50) = NULL AS DECLARE nvarchar(4000) ![]()
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