![]() (ID, Lastname, FirstName, MiddleName,, Ship, ShipRegistry) )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, OPTIMIZE_FOR_SEQUENTIAL_KEY = OFF) ON ĪLTER TABLE. Let’s start by converting the example earlier into 1 INSERT statement. Note that you can only add value clauses for up to 1000 rows in SQL Server 2022. VALUES (value1a, value2a, value3a, valueNa),Įnclosed in parenthesis comprises one row. Here’s the syntax: INSERT INTO table (column1, column2, column3, columnN) Insert Multiple Rows in SQL Server Using VALUESįor the uninitiated, you can use several row values with the VALUES clause. Now when you know how bad it can be, let’s proceed to the first tip. Or examine the execution plans to see how they will impact your system. It depends on your use case, the number of rows, and the requirements. Note that the problems presented here may or may not appear in your specific use case. The approaches you’ll see later are more friendly to your eyes. You’ll see repeated INSERT INTO tables using the same columns. Seeing a lot of INSERT statements compared to better approaches is bad for you if you maintain the code. They don’t want to.Īnd yet, multiple INSERT statements affect you too in the long run. And when this happens, your system will have more waiting. This means that when your transaction holds a lock on a resource, others will have to wait. Then it may cause locking and blocking issues. And it can happen along with other DML commands. But your many INSERT statements may run longer. There can be other factors that can make a database crawl. Performance Impact – Your Database is Now Crawling In this scenario, a rollback or commit of a thousand rows may result in another problem. Not to mention that this is happening in a multi-user environment of thousands of users. Of course, what are 3 rows in SQL Server? But what if this is 3,000 rows? Or maybe 30,000? Don’t fix your mind to just 3 rows. Did you get it? Rollback just 1 INSERT instead of 2. SQL Server will have to roll back the previous 2 INSERT statements.īecause using just 1 INSERT statement for all 3 rows may be easier for SQL Server to rollback. But let’s say the INSERT fails at line 11 from the previous example. That’s atomicity.īut you may say: “If that’s the case, start with BEGIN TRANSACTION and ROLLBACK when an error occurs.” You could be right, but… An Increase in Transaction Overhead May OccurĪdding transactions to cover multiple INSERT statements could be a good idea. It should roll back like nothing happened. If the first step is good and the second went bad and failed, you ended up losing money. Then, add the money to your friend’s account. First, deduct the money from your account. To explain this further, let’s say you want to transfer money from your bank account to your friend’s bank account. If one statement fails, it should be like nothing happened. This is a lack of atomicity in a database management system. Even worse, what if there’s a follow-up INSERT in a child table? If that depends on ID #3, it will also fail. If these statements belong to one transaction unit, it is now inconsistent. Suppose an error occurs running the third INSERT statement in line 11. Suppose you have 3 INSERT statements like the one below. Here’s why using multiple INSERT statements is a terrible idea: Errors May Result in Half-Baked, Inconsistent Data But if you’re doing it the wrong way for quite some time, it’s time to put this aside. Or maybe send new rows from an app into the database. Or you simply need a script to prepare new rows to a brand-new table for the first time. Because you might process a big chunk of data and insert its final values into a table. Using Separate INSERT Statements – How Bad Is It?īefore I give you the hero power-ups for multiple INSERTs, let me convince you first how bad it is.īut if you haven’t done inserting multiple rows in SQL Server, soon you will. So, put on your shiny DBA cape, and let’s begin. ![]() INSERT Multiple Rows in SQL Server From Another Table.Insert Multiple Rows in SQL Server Using VALUES.Using Separate INSERT Statements – How Bad Is It?.In this article, let’s dive into inserting multiple rows in SQL Server correctly. They save the day by freeing the database to a crawling state. But you don’t want it happening in your database.īut let me tell you too that there’s a way to get over this. It gives you an agonizing feeling when your database inserts become like a slow-motion scene in The Matrix. Let me tell you today that it’s a terrible idea. Are you still using multiple INSERT statements to insert multiple rows in SQL Server?
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