Sqlitestudio book code#

The groups table that stores group information.The contacts table that stores contact information.In addition, each contact belongs to one or many groups, and each group can have zero or many contacts.īased on these requirements, we came up with three tables: The requirement is that the email and phone must be unique. Suppose you have to manage contacts using SQLite.Įach contact has the following information: Note that the primary key of a table is a column or a group of columns that uniquely identify each row in the table. Note that the WITHOUT ROWID option is only available in SQLite 3.8.2 or later. A table that contains the rowid column is known as a rowid table. If you don’t want SQLite creates the rowid column, you specify the WITHOUT ROWID option. The rowid column stores a 64-bit signed integer key that uniquely identifies the row inside the table. By default, a row in a table has an implicit column, which is referred to as the rowid, oid or _rowid_ column. Finally, optionally use the WITHOUT ROWID option.Fifth, specify the table constraints such as PRIMARY KEY, FOREIGN KEY, UNIQUE, and CHECK constraints.SQLite supports PRIMARY KEY, UNIQUE, NOT NULL, and CHECK column constraints. Each column has a name, data type, and the column constraint. Fourth, specify the column list of the table.The schema can be the main database, temp database or any attached database. Third, optionally specify the schema_name to which the new table belongs.Attempting to create a table that already exists without using the IF NOT EXISTS option will result in an error.

Second, use IF NOT EXISTS option to create a new table if it does not exist.The name of the table cannot start with sqlite_ because it is reserved for the internal use of SQLite. First, specify the name of the table that you want to create after the CREATE TABLE keywords.

Sqlitestudio book code#

) Code language: SQL (Structured Query Language) ( sql )