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A CREATE statement in SQL creates an object inside of a relational database management system (RDBMS). The types of objects that can be created depends on which RDBMS is being used, but most support the creation TABLEs, INDEXes, USERs, and DATABASEs. Some systems (such as PostgreSQL) allow CREATE and other DDL commands to occur inside of a transaction and thus be rolled back. SQL (commonly expanded to Structured Query Language — see History for the terms derivation) is the most popular computer language used to create, modify, retrieve and manipulate data from relational database management systems. ...
A relational database management system (RDBMS) is a database management system (DBMS) that is based on the relational model as introduced by Edgar F. Codd. ...
In a relational database (RDB), a table is a set of data elements (cells) that is organized, defined and stored as horizontal rows (records) and vertical columns (fields) where each item can be uniquely identified by a label or key or by it’s position in relation to other items. ...
An index is a feature in a database that allows quick access to the rows in a table. ...
A database is a collection of logically related data designed to meet the information needs of one or more users. ...
PostgreSQL is a free object-relational database server (database management system), released under a flexible BSD-style license. ...
A database transaction is a unit of interaction with a database management system or similar system that is treated in a coherent and reliable way independent of other transactions that must be either entirely completed or aborted. ...
In database technologies, a rollback is an operation which returns the database to some previous state. ...
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CREATE TABLE
Perhaps the most common CREATE command is the CREATE TABLE command. The typical usage is:
CREATE TABLE [table name] ( [column definitions] ) [table parameters].
Column Definitions: A comma-separated list consisting of any of the following
- Column definition: [column name] [data type] {NULL | NOT NULL} {column options}
- Primary key definition: PRIMARY KEY ( [comma separated column list] )
- CONSTRAINTS: {CONSTRAINT} [constraint definition]
- RDBMS specific functionality
For example, the command to create a table named employees with a few sample columns would be: A relational database management system (RDBMS) is a database management system (DBMS) that is based on the relational model as introduced by Edgar F. Codd. ...
CREATE TABLE employees ( id INTEGER not ,first_name CHAR(50) null ,last_name CHAR(75) not null ,date_of_birth DATE null ,PRIMARY KEY (id) ); [edit]
See also | Topics in database management systems (DBMS) ( view • talk • edit ) | | Concepts
Database | Database model | Relational database | Relational model | Relational algebra | Primary key - Foreign key - Surrogate key - Superkey
Database normalization | Referential integrity | Relational DBMS | Distributed DBMS | ACID To meet Wikipedias quality standards, this article or section may require cleanup. ...
A database is a collection of logically related data designed to meet the information needs of one or more users. ...
A database model is a theory or specification describing how a database is structured and used. ...
A relational database is a database that conforms to the relational model. ...
The relational model for database management is a data model based on predicate logic and set theory. ...
Relational algebra, an offshoot of first-order logic, is a set of relations closed under operators. ...
In database design, a primary key is a value that can be used to identify a unique row in a table. ...
A foreign key (FK) is a field or group of fields in a database record that point to a key field or group of fields forming a key of another database record in some (usually different) table. ...
Dr. E. F. Codd, the creator of the Relational Model defined a surrogate key as ..Database users may cause the system to generate or delete a surrogate, but they have no control over its value, nor is its value ever displayed to them . ...
A superkey is defined in the relational model as a set of attributes of a relation for which it holds that in all instances of the relation there are no two distinct tuples that have the same values for the attributes in this set. ...
This article or section is in need of attention from an expert on the subject. ...
An example of a database that has not enforced referential integrity. ...
A relational database management system (RDBMS) is a database management system (DBMS) that is based on the relational model as introduced by Edgar F. Codd. ...
According to Elmasri and Navathe (2004, p. ...
-) :-( :-P :-*An acid (often represented by the generic formula HA) is traditionally considered any chemical compound that when dissolved in water, gives a solution with a pH of less than 7. ...
| Objects
Trigger | View | Table | Cursor | Log | Transaction | Index | Stored procedure | Partition A database trigger is procedural code that is automatically executed in response to certain events on a particular table in a database. ...
Originally, in database theory, a view is a read only virtual or logical table composed of the result set of a query. ...
In a relational database (RDB), a table is a set of data elements (cells) that is organized, defined and stored as horizontal rows (records) and vertical columns (fields) where each item can be uniquely identified by a label or key or by it’s position in relation to other items. ...
In database packages, the term cursor refers to a control structure for the successive traversal (and potential processing) of records in a result set as returned by a query. ...
In in the field of databases in computer science, a transaction log (also database log or binary log) is a history of actions executed by a database management system to guarantee ACID properties over crashes or hardware failures. ...
A database transaction is a unit of interaction with a database management system or similar system that is treated in a coherent and reliable way independent of other transactions that must be either entirely completed or aborted. ...
An index is a feature in a database that allows quick access to the rows in a table. ...
To meet Wikipedias quality standards, this article or section may require cleanup. ...
A partition is a division of a logical database or its constituting elements into distinct independent parts. ...
| Topics in SQL
Select | Insert | Update | Merge | Delete | Join | Union | Create | Drop
Comparison of syntax SQL (commonly expanded to Structured Query Language — see History for the terms derivation) is the most popular computer language used to create, modify, retrieve and manipulate data from relational database management systems. ...
A SELECT statement in SQL returns a result set of records from one or more tables. ...
An SQL INSERT statement adds a record to a table in a relational database. ...
An UPDATE statement in SQL changes data in one or more records in a relational database management system. ...
Wikipedia does not have an article with this exact name. ...
A DELETE statement in SQL removes records in a relational database management system. ...
A join combines records from two or more tables in a relational database. ...
UNION Combines the results of two or more queries into a single result set consisting of all the rows belonging to all queries in the union. ...
A DROP statement in SQL removes an object from a relational database management system (RDBMS). ...
This article gives a brief summary of various SQL syntax differences used in popular SQL engines: SQLite MySQL PostgreSQL Firebird / InterBase OpenLink Virtuoso Oracle MSSQL // Data structure definition Escaping identifiers A method to somehow escape identifiers (table, column names, etc), so they do not have to obey regular identifier rules...
| | | Implementations of database management systems | | Types of implementations
Flat file | Deductive | Dimensional | Hierarchical | Object oriented | Temporal
Products
db4o | dBASE | Oracle | Caché | OpenLink Virtuoso | Sybase | Ingres | MySQL | SQLite | Microsoft SQL Server | Essbase | PostgreSQL | DB2 | Informix | Helix database | Teradata | Comparison - relational | Comparison - object-relational A flat file database is described by a very simple database model, where all the information is stored in text files. ...
A deductive database system is a database system which can make deductions (ie: infer additional rules or facts) based on rules and facts stored in the (deductive) database. ...
A dimensional database is one which, rather than storing data in multiple two dimensional tables (as a relational databases does), represents key data entities as different dimensions. ...
To meet Wikipedias quality standards, this article or section may require cleanup. ...
In an object oriented database, information is represented in the form of objects like in object oriented programming. ...
A temporal database is a database management system with built-in time aspects, e. ...
There are very few or no other articles that link to this one. ...
dBASE III The correct title of this article is dBASE. The initial letter is capitalized because of technical restrictions. ...
oracle, see Oracle (disambiguation) An Oracle database, strictly speaking, consists of a collection of data managed by an Oracle database management system or DBMS. The term Oracle database sometimes refers — imprecisely — to the DBMS software itself. ...
Caché is a proprietary M technology-based database management system from InterSystems. ...
The current version of the article or section reads like an advertisement. ...
Sybase SQL Server was the name of Sybase Corporations primary relational database management system product from 1987 to 1995. ...
Ingres (pronounced ingress) is a commercially supported, open-source relational database management system. ...
MySQL is a multithreaded, multi-user, SQL Database Management System (DBMS) with more than six million installations. ...
SQLite is an ACID-compliant relational database management system contained in a relatively small C library. ...
Microsoft SQL Server is a relational database management system (RDBMS) produced by Microsoft. ...
Essbase is a multidimensional database management system (MDBMS) that provides a multidimensional database platform upon which to build analytic applications, ie. ...
PostgreSQL is a free object-relational database server (database management system), released under a flexible BSD-style license. ...
DB2 is IBMs family of information management software products. ...
Informix is a family of relational database management system products from IBM, acquired in 2001 from a company (also called Informix or Informix Software) which dates its origins back to 1980. ...
Helix is a pioneering database management system for the Apple Macintosh platform. ...
Teradata is a relational database management system initially created by the firm with the same name, founded in 1979. ...
It has been suggested that List of relational database management systems be merged into this article or section. ...
The following tables compare general and technical information for a number of object-relational database management systems. ...
| Components
Query language | Query optimizer | Query plan | ODBC | JDBC
Lists
List of object-oriented database management systems
List of relational database management systems
List of truly relational database management systems Query languages are computer languages used to make queries into databases and information systems. ...
The query optimizer is a component of database management system that is used to analyzes queries submitted to database server for execution, and then determines the optimal way to execute the query. ...
A query plan (or query execution plan) is an set of steps used to access information in a SQL relational database management system. ...
In computing, Open Database Connectivity (ODBC) provides a standard software API method for using database management systems (DBMS). ...
Java Database Connectivity, or JDBC, is an API for the Java programming language that defines how a client may access a database. ...
The following is a list of object-oriented database management systems. ...
It has been suggested that List of truly relational database management systems be merged into this article or section. ...
It has been suggested that this article or section be merged into List of relational database management systems. ...
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