5/8/2023 0 Comments Panama hash calculator![]() ![]() A Quick Disclaimer on Potential Collisions While this may not help much with a small table like this, it can be a real time-saver with larger tables. You can now paste this information into your Create Table tool in the Orchestration. This will allow you to copy the Metadata of the table. Then, select the Metadata tab and check the Text Mode box. Before creating your table, simply pull out a Rename tool in your Transformation canvas where you have created your key and rename your columns. Once all of that is completed, you simply need to create the table and run the Upsert. After performing this check, you can now refer to my last blog to create your Upsert. Just as a check, you will want to do a row count on your key value to make sure that you truly have a unique key. A quick note on the COALESCE function in the code: We use this so that, in the event of a null value in the unique field, you will still get a unique key value. Now we simply need to bring in a Calculator tool onto the canvas:įinally, we write the code below to create our key. In this case, it is the Airport Code column. Our first step is to make sure we understand which column, or combination of columns, gives us a unique value. Here is a quick overview of what the workflow will look like when we finish: This makes writing your queries a little faster while improving the performance of your query, and who doesn’t want that? Using a surrogate key is faster when joining two tables than using multiple columns in your join statement. ![]() We use a surrogate key for join performance. If you’re wondering why we need a surrogate key (SK) at all, you’re probably not alone. The MD5 gives us a key value that we can use to reference back from the Fact tables in our data warehouse to the Dimension tables. Using the same workflow, I will discuss how we got the key value using the MD5 hash functionality available in Snowflake and why we need to do it. In my last blog, I discussed how to do an Upsert in Snowflake using Matillion. ![]()
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