8/18/2023 0 Comments Disconnect from sql db sqliteDropping a databaseīecause SQLite does not have a separate server process like other relational databases such as MySQL or PostgreSQL, there is not a need for a DROP DATABASE statement. If it does not exist, then the statement is simply ignored and nothing happens. The behavior it adds makes sure that the command only runs if the table exists. The IF EXISTS statement is optional when dropping a table. Adjusting the previous example will look like this to create the table in test: in your statement to create the table in a database other than main. If you have multiple connections open to databases, you need to specify. It is important to note that the CREATE TABLE statement will create the table you specify in the main database by default. In our example, the addition of PRIMARY KEY to the id field is an example of a table constraint. There is an exception if the constraint affects the interaction of multiple columns instead of a singular column. : Like a column constraint, table constraints are optional to add additional requirements to your data.This ensures no entry is made without this column being populated. In the example, the column constraint Not Null is added to the student_email column. : Column constraints are optional restraints adding additional requirements for the data entering your table. ![]() In the example, a column name would be first_name and its corresponding data type defined by SQLite Data Types is TEXT. : This syntax defines a basic column within the table. ![]() In the example, the is student and should be whatever you intend to name your table.
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