Please note, I have left out all sql-injection prevention code for clarity. Let’s wrap this up with some quick PHP code to demonstrate one way to put a bulk Insert or Update query together, given an array of users. This comes in handy if each row will have a different value for non-key fields, as seen below: INSERT INTO user_preference (user_id, preference_id, value) The Insert or Update syntax also allows you to use the VALUES() function to access the group of values that would be inserted had they not already existed. This is only the tip of the iceberg though. We can do that in a single query as seen in the example below: INSERT INTO user_preference (user_id, preference_id, pref_value) Let’s say we wanted to assign group of user’s a value of ‘true’ to preference_id 1. The user_preference table provides a many-to-many cross-reference table between the two. Assuming we have a users table and a preferences table. Let’s using the following cross-reference table as an example. Okay I admit, I didn’t know until today!īy combining MySQL’s Bulk Insert syntax with the Insert or Update syntax, you are able to reduce a very large number of queries and statements down to one single statement. Many aren’t aware that this technique can also be applied in bulk queries. Most humans, though, get an increasing feeling of impending doom when the clock ticks up towards several hours with no visible progress. It’s essentially a way to leverage a database table’s primary key to reduce the number of queries required to insert or update a record, by eliminating the need to perform a select query first. SQL bulk update in batches Table of contents When you perform a SQL bulk update, you can just press go and wait. The below example shows batch update using the statement.If you’re not familiar with the MySQL Insert or Update statement, check it out before reading on. We cannot remove specific statements using clearBatch method it will delete all the statements from the batch.īelow are the examples which are as follows.This method is used to remove all the statement which was added in batch. We can remove the update statement from the batch using clearBatch() method.Below steps shows how to execute the batch using statement object are as follows.ġ) Create the object of statement using createStatement() method.ģ) Add multiple update statement using addBatch() method.Ĥ) Execute all update statements using executeBatch() method.ĥ) After all execution commits all the changes which was we have done using batch update.Execute batch method is returning the integer of arrays, also it will returning each element of the array.This method is used to start the execution of all update statements in the JDBC batch update method. Execute batch method is used to execute all the statement groups together.This method will add multiple single update statements into the batch. Basically, add batch method is used to add a single statement into the batch.There are two methods used to update multiple statements in the batch.Using PreparedStatemente we can use the PreparedStatement object for the execution of batch update on the database server.Using statement we can use the statement object for the execution of batch update on the database server.
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