Data definition language - Wikipedia, the free encyclopedia. A data definition language or data description language (DDL) is a syntax similar to a computer programming language for defining data structures, especially database schemas. History. SQL- 9. 2 introduced a schema manipulation language and schema information tables to query schemas. These information tables were specified as SQL/Schemata in SQL: 2. The term DDL is also used in a generic sense to refer to any formal language for describing data or information structures. Structured query language.
Structured query language (e. SQL), however, uses a collection of imperative verbs whose effect is to modify the schema of the database by adding, changing, or deleting definitions of tables or other elements.
These statements can be freely mixed with other SQL statements, making the DDL not a separate language. CREATE statement. In the SQL 1. 99.
Many implementations extend the syntax to allow creation of additional elements, such as indexes and user profiles. Some systems, such as Postgre.
SQL and SQL Server, allow CREATE, and other DDL commands, inside a database transaction and thus they may be rolled back. CREATE TABLE statement. The typical usage is.
The Data Definition Language (DDL) is used to create and destroy databases and database objects. These commands will primarily be used by database.
SQL Statement Syntax / Data Definition Statements. Oracle Corporation and/or its affiliates. A data definition language. Oracle data types include CHAR, NCHAR, VARCHAR2. Data Definition Language. Learn how Oracle Big Data technologies deliver a competitive strategy on a unified architecture to solve the.
Title: Oracle Data Definition Language DDL 1 Oracle Data Definition Language (DDL) Dr. University of Central Arkansas; Fall 2008. Structured Query Language/Data Definition. Data definition language (DDL). Forms Data Loader Tool to load data into Oracle Applications 11i / R12 using Macros and Forms Record and Playback.
CREATE TABLE . The types of objects that can be dropped depends on which RDBMS is being used, but most support the dropping of tables, users, and databases. Some systems (such as Postgre.
SQL) allow DROP and other DDL commands to occur inside of a transaction and thus be rolled back. The typical usage is simply. DROP objecttypeobjectname.
For example, a DELETE statement might delete some (or all) data from a table while leaving the table itself in the database, whereas a DROP statement removes the entire table from the database. ALTER statement. The types of objects that can be altered depends on which RDBMS is being used. The typical usage is. ALTER objecttypeobjectnameparameters.
These two statements can be included in a CREATE TABLE or an ALTER TABLE sentence. Other languages. The Codasyl Approach to Data Base Management. The Definitive Guide to SQLite. The create table statement has a special syntax for creating tables from select statements.