To change an enumeration member, the entire table has to be rebuilt using the ALTER TABLE command, which uses a lot of resources and takes a long time.
CORRECT USE OF ENUM IN MYSQL CODE
Though ENUMs propose great advantages for efficient code and storage, its use is generally limited and not widely promoted because of the following reasons: Because the numbers are converted back into the output of the appropriate text, it also offers easily legible searches and output.The allowed list of string values defined in an ENUM data type is not simply stored as strings in the backend but integers which make the data storage compact and dealing with numbers to retrieve and access data is quicker than string lookups.Only allowing a specific list of values ensures that the attribute cannot hold an unknown or invalid value.There are several reasons why ENUM makes the code more efficient. Make sure the column is sorted using ORDER BY CAST(col AS CHAR) or ORDER BY CONCAT(col) to ensure that the lexical order is used rather than the index number.Use one of these methods when using the ORDER BY clause on an ENUM` column to avoid unexpected outcomes: However, we can still obtain desired sorting order. When we use the ORDER BY clause over an ENUM, the values are sorted based on their index values rather than the actual strings. This string differs from a "normal" empty string in that it contains the number 0. The empty string is substituted as a specific error value when you attempt to enter an erroneous value into an ENUM (i.e., a string that isn't on the list of acceptable values). When an ENUM column is marked as NOT NULL, the first item in the list of acceptable values is used as the field's default value. You can also specify NULL as the default value if you want to allow NULL values in the ENUM column. In this case, the default value for the color column is one of the allowed ENUM values.
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