How To Drop an Index

Q

How To Drop an Index? - Oracle DBA FAQ - Managing Oracle Table Indexes

✍: FYIcenter.com

A

If you don't need an existing index any more, you should delete it with the DROP INDEX statement. Here is an example SQL script:

CREATE TABLE student (id NUMBER(5) PRIMARY KEY,
  first_name VARCHAR(80) NOT NULL,
  last_name VARCHAR(80) NOT NULL,
  birth_date DATE NOT NULL,
  social_number VARCHAR(80) UNIQUE NOT NULL);
Table created.

CREATE INDEX student_birth_date ON student(birth_date);
Index created.

SELECT index_name, table_name, uniqueness 
  FROM USER_INDEXES WHERE table_name = 'STUDENT';
INDEX_NAME              TABLE_NAME            UNIQUENES
----------------------- --------------------- ---------
SYS_C004129             STUDENT               UNIQUE
SYS_C004130             STUDENT               UNIQUE
STUDENT_BIRTH_DATE      STUDENT               NONUNIQUE 

DROP INDEX STUDENT_BIRTH_DATE;
Index dropped.

2007-05-02, 5017👍, 0💬

What Happens to Indexes If You Drop a Table
What Happens to Indexes If You Drop a Table? - Oracle DBA FAQ - Managing Oracle Table Indexes If you drop a table, what happens to its indexes? The answer is that if a table is dropped, all its indexes will be dropped too. Try the following script to see yourself: CREATE TABLE student (id NUMBER(5) ... 2007-05-02, 7515👍, 0💬

What Happens to the Indexes If a Table Is Recovered
What Happens to the Indexes If a Table Is Recovered? - Oracle DBA FAQ - Managing Oracle Table Indexes If you dropped a table, and recovered it back from the recycle bin, what happens to its indexes? Are all indexes recovered back automatically? The answer is that all indexes will be recovered, if yo... 2007-05-03, 5930👍, 0💬

How To Rebuild an Index
How To Rebuild an Index? - Oracle DBA FAQ - Managing Oracle Table Indexes If you want to rebuild an index, you can use the "ALTER INDEX ... REBUILD statement as shown in the following SQL script: SELECT index_name, table_name, uniqueness FROM USER_INDEXES WHERE table_name = 'EMPLOYEES'; INDEX_NAME T... 2007-04-27, 5540👍, 0💬

How To List All Indexes in Your Schema
How To List All Indexes in Your Schema? - Oracle DBA FAQ - Managing Oracle Table Indexes If you log in with your Oracle account, and you want to get a list of all indexes in your schema, you can get it through the USER_INDEXES view with a SELECT statement, as shown in the following SQL script: SELEC... 2007-05-02, 5325👍, 0💬

Can You Drop an Index Associated with a Unique or Primary Key Constraint
Can You Drop an Index Associated with a Unique or Primary Key Constraint? - Oracle DBA FAQ - Managing Oracle Table Indexes You can not delete the index associated with a unique or primary key constraint. If you try, you will get an error like this: ORA-02429: cannot drop index used for enforcement o... 2007-05-02, 5270👍, 0💬

What Is an Index Associated with a Constraint
What Is an Index Associated with a Constraint? - Oracle DBA FAQ - Managing Oracle Table Indexes An index associated with a constraint because this constraint is required to have an index. There are two types of constraints are required to have indexes: UNIQUE and PRIMARY KEY. When you defines a UNIQ... 2007-05-02, 5221👍, 0💬

How To Rename an Index
How To Rename an Index? - Oracle DBA FAQ - Managing Oracle Table Indexes Let's say you have an existing index, and you don't like its name anymore for some reason, you can rename it with the ALTER INDEX ... RENAME TO statement. Here is an example script on how to rename an index: CREATE TABLE studen... 2007-05-02, 5201👍, 0💬

How To Run SQL Statements through the Web Interface
How To Run SQL Statements through the Web Interface? - Oracle DBA FAQ - Managing Oracle Table Indexes If you don't like the command line interface offered by SQL*Plus, you can use the Web interface to run SQL statements. Here is how: Open your Web browser to http://localhost:8080/apex/ Log in to the... 2007-05-02, 5060👍, 0💬

How To Create a Table Index
How To Create a Table Index? - Oracle DBA FAQ - Managing Oracle Table Indexes If you have a table with a lots of rows, and you know that one of the columns will be used often a search criteria, you can add an index for that column to in improve the search performance. To add an index, you can use th... 2007-05-02, 5058👍, 0💬

All rights in the contents of this web site are reserved by the individual author. fyicenter.com does not guarantee the truthfulness, accuracy, or reliability of any contents.