The difference between blob and clob in oracle

The main differences between BLOB (Binary Large Object) and CLOB (Character Large Object) in Oracle are: 1. BLOB stores binary data, while CLOB stores character data; 2. The maximum size of BLOB is 4 GB, and the maximum size of CLOB is 4 GB or 32 times the database block size; 3. BLOB does not support indexes, while CLOB supports part of the index; 4. Querying BLOB loads the entire BLOB, while querying CLOB only loads the first 4000 characters; 5. BLOB is stored in the LOB segment , and CLOB

The difference between BLOB and CLOB in Oracle

Question: Oracle What is the difference between BLOB and CLOB?

Answer: BLOB (Binary Large Object) and CLOB (Character Large Object) are large objects that store binary files and text files in Oracle database. The main differences between them are as follows:

1. Data type

• BLOB stores binary data such as images, audio or video files.
• CLOB stores character data, such as text files or XML documents.

2. Size Limitations

• The maximum size of a BLOB is 4 GB.
• The maximum size of a CLOB is 4 GB or 32 times the database block size, whichever is smaller.

3. Index

• BLOB does not support indexing.
• CLOB supports a subset of indexes, but only the first 4000 characters.

4. Query efficiency

• When querying a BLOB, Oracle will load the entire BLOB into memory, which may seriously affect performance.
• When querying a CLOB, Oracle only loads the first 4000 characters, which usually does not affect performance.

5. Storage

• BLOBs are stored in specialized segments, called LOB segments.
• CLOBs are stored in tablespaces, along with other table data.

6. Purpose

• BLOB is usually used to store images, videos, audio and binary files.
• CLOBs are commonly used to store text, HTML, XML, and JSON data.

The following is a table summarizing the key differences between BLOBs and CLOBs:

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