How to query synonyms using Oracle

Oracle is one of the most popular relational database management systems in the world. It provides an efficient, reliable, and highly secure method to store and manage large amounts of data. In Oracle, querying synonyms is a very important function. In this article, we will learn how to use Oracle to query synonyms.

What are synonyms?

A synonym refers to a name defined in the database that can be used to replace another name and reference it during queries. Synonyms can be any type of database object, such as tables, views, stored procedures, etc. Using synonyms makes it easier for programmers and database administrators to manage database objects because they avoid using names that are too long or complex.

How to create synonyms?

In Oracle, creating synonyms is very simple. Use the following syntax to create synonyms:

CREATE SYNONYM synonym_name FOR object_name;

Where, synonym_name is the name of the synonym, object_name is the name of the object to be referenced, such as table name, view name, stored procedure Name etc. For example, to create a synonym synonym1 that refers to table table1, you can use the following command:

CREATE SYNONYM synonym1 FOR table1;

After the synonym is created, it can be queried together with the referenced object, as follows Shown:

SELECT * FROM synonym1;

This will select all rows from the referenced table table1.

Query created synonyms

To query created synonyms in Oracle, you can use the following statement:

SELECT * FROM ALL_SYNONYMS;

In query In the results, you will see a list of all synonyms that exist in the database, including information such as the synonym's name, object name, and owner name.

If you only want to find information about a specific synonym, you can use the following syntax:

SELECT * FROM ALL_SYNONYMS WHERE synonym_name='synonym1';

In this example , the query name is the synonym of synonym1.

Delete synonyms

If you need to delete synonyms from the Oracle database, you can use the following command:

DROP SYNONYM synonym_name;

For example, to delete the name To make a synonym for synonym1, you can use the following command:

DROP SYNONYM synonym1;

This will delete the synonym1 synonym and all its attributes.

Summary

In this article, we learned how to create, query and delete synonyms in Oracle. Synonyms are a very useful feature in Oracle database management that enable programmers and administrators to manage database objects more easily and avoid the use of complex names. By using the methods provided in this article, you can successfully create, query, and delete synonyms to better manage your Oracle database.

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