But in many cases this only provides a modest improvement as each UPDATE operation still requires a round-trip communication with the database server.
In the case where the application server and database server are on different hosts, the round-trip will involve network latency as well.
The dominant factor in the time taken to complete the overall operation tends to be the “admin” work in conveying the application’s intention to the database server rather than the actual updates to the database.
We can easily contrive for an “updates” table to exist by creating a temporary table and populating it.
It is relatively straightforward to populate a table with multiple rows with just one query (or at least, far fewer queries than the number of rows desired).
But if there are a large number of rows that require an update, then the overhead of issuing large numbers of UPDATE statements can result in the operation as a whole taking a long time to complete.
The traditional advice for improving performance for multiple UPDATE statements is to “prepare” the required query once, and then “execute” the prepared query once for each row requiring an update.
Earnest Hemingway, A Farewell To sure, set up a straw man outlier scenario, and you can justfy ~anything~ where was the hint of those conditions in the original post, sean? The real answer, and especially in sql, is that it depends.
As for a billion project settings, I know personally that America's biggest oil company has a EAV system designed to do just that. I moved a half billion records yesterday in DEV in 4999 record batches.In this walkthrough, you use individual controls to bind to the parent table; this requires the additional code to commit the new parent record.If the parent records were displayed in a complex binding control like the Depending on your application requirements, there are several steps that you may want to perform after you save related data in the Windows-based application.So, given a list of updates to apply we could effect them using the following steps: So in the example above we can reduce five statements to four. But now the number of statements is no longer directly dependent on the number of rows requiring updates.Even if we wanted to update a thousand rows with different values, we could still do it with four statements.and we could persuade the database server to apply those updates to the target table?