How To Drop an Index

Q

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

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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, 4852👍, 0💬

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Can You Drop an Index Associated with a Unique or Primary Key Constraint
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What Is an Index Associated with a Constraint
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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, 4999👍, 0💬

How To Create a Table Index
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How To Drop an Index
How To Drop an Index? - Oracle DBA FAQ - Managing Oracle Table Indexes 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(8... 2007-05-02, 4853👍, 0💬

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