Let’s look at the query and the results and then examine how it works. We want to query the Order table and to include the Company name instead of just the CompanyID. Ok, now that we have re-capped everything, let’s look at how to use the JOIN clause to mimic the behavior of VLOOKUP in SQL – if you want to follow along, the SQL database is here. How to use the JOIN clause to mimic VLOOKUP in SQL To summarize: a JOIN clause is used in SQL to combine rows from two or more tables, based on a related column between them. Almost all databases partition the data in this way, so learning how to join tables is very important. Of course, now that the data is in different tables, to perform any meaningful queries, we’re going to need to include the JOIN clause in most of our queries. It would be much better to partition this one big table into smaller tables and relate them to each other with ID columns. However, if there were hundreds of thousands of rows, then it becomes inefficient to query. It provides lots of useful information, and we would be able to draw some interesting reports from it, such as ‘Sales Totals per Sales Rep’ or ‘Sales Totals per Region’. The table below shows some information about some sales orders. This is called ‘data partitioning’ (specifically vertical partitioning) and is best understood with the simple example below. Instead, it is much better to structure the data in multiple related tables. Why can’t the data be stored together in one table? The reason is that for large databases, it is computationally inefficient to search ‘wide’ tables (ie tables with lots of columns). Specifically, we’re going to show the equivalent of Excel’s VLOOKUP in SQL.īefore we continue, let’s just remind ourselves why we need to use the JOIN clause so often in SQL to merge data from different tables. In this article, we’re going to look at a wider range of scenarios and introduce some variations of the simple JOIN clause. In the introductory article, we showed you how to use the JOIN clause in a simple SQL query to get data from two related tables. Check out our article here to learn more about XLOOKUP. It adds a couple of cool new features and addresses some limitations in VLOOKUP. TIP : Microsoft introduced XLOOKUP in late 2019 as the replacement for VLOOKUP. I can add a similar formula in cell E4 and then copy it down to populate the table: VLOOKUP(B4,$G$4:$J$13,3,FALSE) return the value in the second column of range G4:J13 where the value in B4 matches a value in the first column of range G4:J13.In cell D4, we can enter the following to populate the corresponding Company for CompanyID 1001: VLOOKUP(B4,$G$4:$J$13,2,FALSE) We therefore need to merge (or join) these tables. The company name (and some other information) is stored in a separate table. There is a ‘Sales’ table which gives me sales amounts for companies, but it only references the CompanyID’s not the names. The go-to function for this is VLOOKUP (or the MATCH / INDEX functions).įor those of you less familiar with VLOOKUP, here is a simple example to explain it. If you work in Excel on a day-to-day basis there’ll often be times when you need to wrangle data from a bunch of sources into a merged summary table for reporting or aggregation purposes. Ask a range of Excel users what their favorite or most used function is, and chances are that a lot of them will say “VLOOKUP”.
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