Data Scheme objects
Table 7.1 Oracle 9i data scheme objects
Name |
Meaning |
Data tables |
A table is a database object that holds user data. Tables in a database can be divided into system tables and user tables, depending on the functionality. The system table is used to store data that manages user data and the database itself, also known as the Data dictionary table, the user table is used to store the user's data information, and the default data table is the user table. |
Index |
An index is a directory of books, and it allows you to quickly find what you need. Indexes are always closely related to data tables |
View |
A view is a way to view data in a datasheet, and the main purpose of using a view is to ensure the security of the datasheet and the complexity of the hidden data. The view is not a datasheet, just a definition of some SQL query statement |
Manage Scenario Objects
Table 7.2 Oracle 9i Management Scenario Objects
Name |
Meaning |
Database links |
Manage the logon user name, password, and database location for the Distributed Network Database server environment |
Synonyms |
Synonyms are used to hide the user name and datasheet name of a table, providing security |
Sequence |
A scheme object that directly produces a unique sequential sequence number |
Materialized view |
A datasheet that contains query results for one or more data tables, and rapid |
Materialized View Log |
A datasheet that records all the changes that were made to the datasheet after the last snapshot was refreshed, and rapid the log |
Refresh Group |
Set the time and condition of all objects under the database user to refresh |
Cluster |
A management structure that is stored in a data table that is related to each other and has the same field |
Table Types |
Table types can also be called nested table types, which can contain nested tables in the definition of a table |
Pl/sql Programming Solution Object
Table 7.3 Oracle 9i Pl/sql Programming Solution Object
Name |
Meaning |
Process |
Procedures are also called stored procedures, which are grouped together by SQL statements and PL/SQL statements to perform an executable unit of a task, similar to modules in advanced programming languages |
Function |
Functions and procedures are structurally similar. The difference between procedure and function is that the function always returns a single value to the caller, and the procedure has no value returned to the caller |
Program Package |
A package is also called a packet, which is defined as a set of procedures, functions, variables, and SQL statements that are lumped into a single unit. |
Program Package Body |
The package body is also called the package body, which is the same as the corresponding package, and the detailed execution code of the function and procedure declared within the package. |
Trigger |
A trigger is a special type of stored procedure that consists of a number of SQL statements that are used primarily to enforce a mandatory business rule or requirement, but do not return a result |
Object type |
Objects are the basic concepts of object-oriented analysis and design, objects with the same attributes and services are called classes, and classes are referred to as Object types in Oracle 9i, and are also called abstract data types in some database books. |
Array type |
In Oracle 8, it is called a variable group. Provides custom array functionality, including the number of array elements, the type of elements, length and precision, and so on. |
Advanced queues |
A data storage structure, characterized by advanced first out |
Java source |
Some Java source code that can be invoked as a Java share process with each other |
- dimensional |
A logical structure for classifying data in a data warehouse |
How to view Scenario objects
The interface shown in Figure 7.1. The 21 scenario objects in Oracle 9i are enumerated.