错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Tables and Constraints

  • Michelle Malcher,
  • Darl Kuhn

摘要

The next logical step is to create objects in the database. Usually, the objects created for an application are tables, constraints, and indexes. A table is the basic storage container for data in a database. You create and modify the table structure via DDL statements, such as CREATE TABLE and ALTER TABLE. You access and manipulate table data via DML statements (INSERT, UPDATE, DELETE, MERGE, SELECT).