The role of a database index is to quickly access specific information in a database table. Indexes can improve the speed of data search and retrieval, speed up the connection between tables, and improve the efficiency of the server in processing related search requests.
An index is a structure that sorts the values of one or more columns in a database table. Indexes can be used to quickly access specific information in a database table. If you want to find a specific employee by his or her last name, an index can help you get the information faster than searching for all the rows in the table.
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One of the main purposes of the index is to speed up the retrieval of data in the table, that is, to help information searchers find the matching information as quickly as possible An auxiliary data structure for the record ID of the constraint.
Advantages of indexing:
By establishing an index, you can greatly improve the speed of obtaining the required information in the database, and at the same time, it can also improve the efficiency of the server in processing related search requests. From this In terms of aspects, it has the following advantages:
When designing a database, by creating a unique index, a one-to-one mapping relationship can be formed between the index and information, increasing the uniqueness of the data. .
It can improve the speed of data search and retrieval, which is in line with the original intention of establishing the database.
It can speed up the connection speed between tables, which plays an important role in improving the reference integrity of data.
In the process of information retrieval, if grouping and sorting clauses are used, indexing can effectively reduce the grouping and sorting time required in the retrieval process and improve retrieval efficiency.
After the index is established, the optimization hider can be used during the information query process, which is of great significance for improving the performance of the entire information retrieval system.
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