![]() ![]() We will also look at various operations on the tables, see how to use most common clauses such as WHERE, GROUP BY, HAVING and learn how to join two or more tables.Struggling with multiple programming languages? No worries. In the next article, we will see how to insert data in a table, fetch specific records and delete/alter tables. To execute the query, go to F9 (Figure 5). In the parentheses is the list that defines each column in the table and what kind of data it displays. CREATE TABLE is the keyword that tells the database system what you want to do. User defined integrity: Implements certain business policies that are not related to the integrity of the entity, domain, or reference.Reference integrity: Rows cannot be deleted other records use them.Domain integrity: Applies valid entries for a given column, limiting the type, format or range of values.Entity integrity: There are no duplicate rows in a table.Default: Provides a default value for a column when none is specified.Check: Ensures that all values in a column satisfy certain conditions.Unique: Ensures that all values in a column are different.Foreign key: Uniquely identifies a row/table in any other database table. ![]() Primary key: Uniquely identifies each row in a database table.Not null: Ensures that the column cannot have a null value.Column-level restrictions apply to a single column, while table-level restrictions apply to the entire table. This ensures the accuracy and reliability of the database data.Ĭonstraints can be at column or table level. They are used to limit the type of data that can be included in a table. It doesn’t mean ‘zero’ value but just the lack of a value.Ĭonstraints are the rules that apply to the data columns in a table. ‘Null’ value: A ‘null’ value in a table is a value that appears empty. For example, a column in the ‘Customer’ table is NAME, which represents the names of all the customers. Row: A row (records or tuple) in a table represents a single, implicitly structured data.Ĭolumn: A column (or field) in a table is a vertical entity that contains all the information associated with a specific field. It is the most common and simplest form of storing data in a RDBMS.Īn example of a ‘Customer’ table is given in Figure 3. This table is a collection of related data items, and consists of rows and columns. To create a database, click on Database > Add Database (Ctrl + O) > New_Database Table: Data is stored in database objects called tables in RDBMS. A phone book uses a database to store peoples’ names, phone numbers, contact details and addresses. As an example, an electrical service provider uses a database to manage billing, customer issues and their addresses. A picture, image, file, etc, can also be considered data.Īn SQL Server database consists of a collection of tables that store a specific set of structured data. For example, your name, address, salary, date of birth, etc, is some of the data related to you. For example, another script language could be added along with it.ĭata can be facts related to any object. Plugins: SQLite Studio supports plugins of different categories. Just download the package, unzip and run it. Portable distribution: No installation is required. Multi-platform: Works on three main platforms: Windows, MacOS X, Linux. Hassle-free multiple databases: SQL statements that refer to multiple databases can be executed in a single query, thanks to the transparent database connection mechanism built into the SQL editor of SQLite Studio.ĭrag and drop between databases: It is possible to drag objects (tables, indexes,…) between databases to copy or move them, with or without data. Advanced SQL Code Editor: The SQL Editor window highlights and offers hints on SQL syntax, providing a print code formatter, and flags syntax errors. We’ll start with the basics - what is a database and how to create one what are tables, rows, columns, constraints, and how to create a table and execute it with some keyboard shortcuts for quick results.įeatures of SQLite Studio Free and open source: It is free for everyone, for any purpose (including commercial). This article provides the basics needed to effectively use SQLite in any database environment. SQLite Studio is an open source, compact, standard and easy to install cross-platform database management system.
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