![]() However, they are ordered by their index numbers and not by their ENUM values.įor example, this query shows orders sorted by their status. Queries can be ordered using the ENUM values. Here’s a query that finds all orders that are delivered (index of 4) SELECT id, order_date, status The same query can be written using the index value of 1. We can see that only the orders that are Not Started are shown. Here’s a query to find all orders that are Not Started: SELECT id, order_date, status You can filter them on either the ENUM value (the text value) or the index. You can work with ENUM values in a WHERE clause. Non-Strict SQL mode: an empty string value ” and an index of 0 are used.The result depends on if your MySQL server is in strict SQL more or non-strict SQL mode: Data truncated for column ‘status’ at row 1 What if we insert an invalid value (one that does not exist in the ENUM list)? INSERT INTO cust_order (id, order_date, status)Įrror Code: 1265. if NULLS are not allowed (there is a NOT NULL constraint), the value used is the one with an index of 1 (the first value).If NULLs are allowed (there is no NOT NULL constraint), the NULL value is valid and it is inserted.The result depends on if the column is allowed NULL values (i.e. What if we insert a NULL value? INSERT INTO cust_order (id, order_date, status) We can insert a different value into the table: INSERT INTO cust_order (id, order_date, status) INSERT INTO cust_order (id, order_date, status) This next statement inserts an order using the index of 1, which would translate to a status of Not Started. To insert values into an ENUM column you can refer to either the text value itself or the numeric index.įor example, this statement inserts a new record using the text value of Not Started: INSERT INTO cust_order (id, order_date, status) We’ll see how we can work with these values shortly in this guide. So, here’s how this example would translate Value stored in table This has the advantage of saving space: a single number is smaller to store than many text characters. These numbers correspond to the values in the ENUM specification here. The values stored in this field are actually numbers, not text values. Status ENUM('Not Started', 'Processing', 'In Transit', 'Delivered') Here’s an example of a customer order table that stores information about orders placed on an eCommerce website. ![]() This is easily done using a Create Table statement. To create an ENUM data type, you add a column with the ENUM data type to a table: ENUM('value 1', 'value 2'. Let’s take a look at how you create an ENUM data type. A check constraint just limits the values to those you specify. Values are stored as numbers but can be viewed as their corresponding text value. This description sounds a lot like a check constraint on a table, but there is a difference.Īn ENUM data type actually defines how the data is stored. in a Create Table statement), and store these values in an efficient way.Įnum is short for enumeration, which is a term in software development for a valid list of values. It lets you specify a list of valid values when you set the data type (e.g. Difference Between ENUM and SET in MySQL.
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