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Approach #2 is better, if you don't want your trigger to fire if column is being changed to the same value. Two MacBook Pro with same model number (A1286) but different year. One of the daunting parts of writing updates, especially with a large number of columns, is figuring out which records actually changed, and only updating those records. The user has the possibility to change it. Copy the n-largest files from a certain directory to the current one. Why does Acts not mention the deaths of Peter and Paul? This is because of the need to then filter on all of those columns, and non-equality predicates are generally not able to use index seeks, and the overhead of table & index writes and transaction log entries as mentioned above. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. In 5e D&D and Grim Hollow, how does the Specter transformation affect a human PC in regards to the 'undead' characteristics and spells? I think .Update is not available in Entity Framework, It's nifty, but I've found it doesn't really help when using EF in conjunction with Web API 2, because the. Really! I'm learning and will appreciate any help, Simple deform modifier is deforming my object. My first blog. composite types in there, data validation, etc). Lets use EXISTS and EXCEPT to find all records which changed. How are engines numbered on Starship and Super Heavy? Whereas most update stored procedures I have created just updated all of the fields WHERE key=value, they want to update individual fields. It appears that PostgreSQL on Amazon RDS will also just blindly write the rows, even if they are unchanged. My estimate is once every 15ms at peak times. If you want to update the object in question, it should be through the use of the class I'm writing. Is there such a thing as "right to be heard" by the authorities? Which reverse polarity protection is better and why? Making statements based on opinion; back them up with references or personal experience. Generating points along line with specifying the origin of point generation in QGIS, Canadian of Polish descent travel to Poland with Canadian passport. IF EXISTS (Select 1 from Table where ID =@ID AND HashValue=Sha256(column1+column2)) GOTO EXIT ELSE, sqlperformance.com/2012/10/t-sql-queries/conditional-updates, How a top-ranked engineering school reimagined CS curriculum (Ep. Here weve got some sample dataWe have a customer table, where we store the customers first, middle and last name, and their birth date. Customizing the setters is simply not an option. The problem is that we're dealing with properties, not fields - and they are in a sealed class, so I don't have access to any underlying fields. It is up to the application to enquire and react. Simply enabling either type of row versioning isolation level on a database always causes the extra logging and flushing. Why does Acts not mention the deaths of Peter and Paul? Because of those complexities, it doesn't usually make sense to do this kind of row-by-row, field-by-field comparison as you're doing the updates. It does NOT care if the value is the same as before. Are these quarters notes or just eighth notes? What is the symbol (which looks similar to an equals sign) called? If you want to change the field to 'hello' only if it is 'bye', use this: If you want to update only if it is different that 'hello', use: Is there a reason for this strange approach? The best answers are voted up and rise to the top, Not the answer you're looking for? Any really, whatever strategy you choose is probably totally fine. not actually updating any rows (hence nothing to write to disk, not even minimal log activity), and, taking out less restrictive locks than what are required for doing the actual update (hence better for concurrency) (, the amount of contention on the table being updated, if there are UPDATE Triggers on the table being updated (as noted by Mark in a comment on the Question). Yet another option is Reflection whereby you can do the same thing dynamically (Edit: see the Single Smart-Update Method in Dan1701's answer). Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. If you indexed these columns, you could easily tell if row data has changed by comparing the MAX(timestamp) to its value since the last time it was evaluated.