A generated column can reference other columns including other generated columns within the same table as long as it does not reference itself.A generated column can be a part of one or more indexes.A generated column can have NOT NULL, CHECK, UNIQUE, and FOREIGN KEY constraints.SQLite will convert the value from the expression to that data type using the same affinity rules as for regular columns. A generated column can have a datatype.Generated columns have the following features: SQLite generated column exampleįirst, create a table called products by using the following CREATE TABLE statement:Īs you can see clearly from the output, the value of the net_price column is calculated based on the values of the price, discount, and tax columns. In practice, you use the STORED option when you want to optimize for reading and the VIRTUAL option when you want to optimize for writing.
SQLite uses the VIRTUAL by default when you don’t explicitly specify VIRTUAL or STORED in the generated column declaration. SQLite updates the values of the STORED generated column when you write to the database. In other words, the STORED generated column takes up spaces in the database file. In case a generated column is STORED, SQLite stores the values of the column physically. Instead, when you read values from the generated column, SQLite computes these values based on the expression specified in the column declaration. If a generated column is VIRTUAL, SQLite doesn’t store the values of the column physically.
#Sqlite uuid generator code
Column_name data_type AS expression Code language: SQL (Structured Query Language) ( sql )Ī generated column can be either VIRTUAL or STORED.
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