![]() | Bottomless Coffee Mugs (4 Pack) | 9.99 | 9 | 90 | | Smash 2000 Sledge Hammer | NULL | 7 | NULL | | Right handed screwdriver | 25.99 | 12 | 312 | | ProductName | ProductPrice | Quantity | TotalValue | Now let’s run the previous query again, but this time we’ll add the newly created generated column to our query: SELECT That gives us the total value of all products in stock. In this case, our computed column multiplies the Quantity column by the ProductPrice column. We could have optionally included GENERATED ALWAYS (before the AS keyword) to make the definition more explicit. That’s all we needed to do in order to create a generated column. Here’s how we could do that: ALTER TABLE Products ADD TotalValue INT AS (Quantity * ProductPrice) We could add a generated column to this table that calculates each product’s price by the quantity in stock. We also have a Quantity column that contains the number of each product in stock. Here, we have a list of products and their prices. | Bottomless Coffee Mugs (4 Pack) | 9.99 | 9 | | Chainsaw (Includes 5 spare fingers) | 245.00 | 21 | | Right handed screwdriver | 25.99 | 12 | | ProductName | ProductPrice | Quantity | ![]() Suppose we run the following query against a table called Products: SELECT ![]() In MySQL, generated columns have the following syntax: col_name data_type AS (expr) This article contains an example of adding a generated column to a table in MySQL.Īlso known as computed columns, generated columns usually contain values that are dependent on other factors (such as the values in other columns).Ĭreating (or adding) a generated column in MySQL is basically the same as creating a normal column, except that the definition of the generated column contains an expression that determines the column’s value. ![]()
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