![]() ON DELETE CASCADE ON UPDATE NO ACTION Code language: SQL (Structured Query Language) ( sql ) ON DELETE CASCADE ON UPDATE NO ACTION Code language: SQL (Structured Query Language) ( sql ) FOREIGN KEY (group_id) Therefore, you use FOREIGN KEY constraint to define a foreign key for each column. In addition, the contact_id and group_id are the foreign keys. To add the table primary key constraint, you use this syntax: PRIMARY KEY (contact_id, group_id) Code language: SQL (Structured Query Language) ( sql ) The contact_groups table has a primary key that consists of two columns: contact_id and group_id. The following statement creates contact_groups table: CREATE TABLE contact_groups( The group_id column is the primary key column. The groups table is quite simple with two columns: group_id and name. The following statement creates the groups table: CREATE TABLE groups ( The email and phone are unique therefore we use the UNIQUE constraint for each column. It means that you must provide values when you insert or update rows in the contacts table. The first_name and last_name columns have TEXT storage class and these columns are NOT NULL. The contact_id is the primary key of the contacts table.īecause the primary key consists of one column, you can use the column constraint. ) Code language: SQL (Structured Query Language) ( sql ) The following statement creates the contacts table. The following database diagram illustrates tables: contacts groups, and contact_groups. The contact_groups table that stores the relationship between contacts and groups.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.To create a new table in SQLite, you use CREATE TABLE statement using the following syntax: CREATE TABLE. Introduction to SQLite CREATE TABLE statement Summary: in this tutorial, you will learn how to create new tables using SQLite CREATE TABLE statement using various options. Students may receive one year free by visiting. Special offer for Daring Fireball readers: Save 20 percent on any SQLPro Studio web store purchase using the promo code GRUBER, or download a free trial on the iOS App Store. This is how you do a cross-platform suite of serious pro apps. ![]() Dark Mode support on Mac and iOS? Of course. The developer, Kyle Hankinson of Hankinsoft Development, has been working on this suite of apps for years now, frequently updates them, and is incredibly responsive to users. It handles everything from schema design to browsing and editing records, with full syntax coloring. Yes, SQLPro Studio has an excellent SQL database client for iPhone. SQLPro Studio is an exquisite truly native app for developers working with SQL databases - MySQL, PostgreSQL, Microsoft SQL Server, and the one I use the most, SQLite.īut native for what? All Apple platforms: Mac, iPad, and even iPhone. That’s especially true for professional tools. Look, it is no surprise to anyone reading this that I care deeply and feel strongly about using truly native Mac and iOS apps. My thanks to SQLPro Studio for sponsoring last week at DF. ![]()
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