What is the Lob data type? What are the limitations of these data types in JDBC?

王林
Release: 2023-08-29 17:29:02
forward
814 people have browsed it

什么是 Lob 数据类型? JDBC 中这些数据类型有哪些限制?

BLOBare binary large objects that can hold variable amounts of data with a maximum length of 65535 characters

They are used to store large amounts of binary Data, such as images or other types of files.

CLOBTypically standing for Character Large Object, SQL Clob is a built-in data type used to store large amounts of text data. Using this data type, you can store up to 2,147,483,647 characters of data.

The Blob and Clob data types together are called LOB (large object) data types. The following are restrictions on these data types.

  • Cannot compare:We cannot compare CLOB or BLOB data types, i.e. you cannot combine these data types with operators =, !=.

  • Unsortable:You cannot arrange BLOB or CLOB data types in order, that is, you cannot determine which of the two data types is larger or smaller BLOB or CLOB data type. In short, you cannot use , >= with BLOB or CLOB types.

  • These cannot be used as primary key or index values

  • Subjects such as DISTINCT, GROUP BY and ORDER BY are not allowed on BLOB or CLOB data types sentence.

  • Implicit conversion of BLOB or CLOB to other data types is not possible.

The above is the detailed content of What is the Lob data type? What are the limitations of these data types in JDBC?. For more information, please follow other related articles on the PHP Chinese website!

source:tutorialspoint.com
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template
About us Disclaimer Sitemap
php.cn:Public welfare online PHP training,Help PHP learners grow quickly!