![]() ![]() Quantity INTEGER NOT NULL CHECK(Quantity > 10) SQLite check constraint a condition to check an inserted value, if the value doesn’t match the condition, it won’t be inserted. Note that, this applies on the values of the column “EmployeeId” only. ![]() This will enforce the “EmployeeId” value to be unique, no duplicated values will be allowed. SQLite Unique constraint it will prevent duplicate values among all the values of the column.įor example: EmployeeId INTEGER NOT NULL UNIQUE If you write an insert statement, and you didn’t specify any value for that column, the column will have the value 0. SQLite Default constraint if you don’t insert any value in a column, the default value will be inserted instead.įor Example: ColumnName INTEGER DEFAULT 0 SQLite Not null constraint prevents a column from having a null value:ĬolumnName INTEGER NOT NULL DEFAULT Constraint To create a combination of columns as a primary key:.There are a lot of different ways to define a primary key on a table like: The primary key can be applied to only one column or on a combination of columns, in the latter case, the combination of the columns’ values should be unique for all the tables’ rows. SQLite Primary KeyĪll the values on a primary key column should be unique and not null Columns constraints are defined when creating a table, in the column definition. Column constraints enforce constraints and rules to the values inserted on a column in order to validate the inserted data. ![]()
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