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What are the advantages and disadvantages of logical models commonly used in databases? Many people don't know much about it. In order to let everyone know more about the logical model commonly used in databases, I summarized the following contents for everyone and looked down together.

What are the logical models used in databases?

The most commonly used logical models in the database domain are: hierarchical model (tree diagram), network model (net, graph), and relational model.

1. Hierarchical model:

Advantages:

1. Clear structure for easy viewing of relationships between entities

2. simple operation

3. high query efficiency

Disadvantages:

1. Low structural flexibility. When an entity needs to be updated or modified, other data will be affected.

2. Increased administrative burden on DBMS

2. Network model:

Advantages:

1. Allow a single node to have more than one parent

2. There can be two or more nodes without a parent.

3. A true reflection of the real world.

Disadvantages:

1. Complex contact, difficult to achieve, database maintenance and reconstruction difficult

3. Relationship model:

Advantages:

1. Simple and clear structure

2. relatively independent

3. convenient operation

4. with solid mathematical foundations.

Disadvantages:

Compared with hierarchical model, query efficiency is lower, and query burden of system is increased.

What are the advantages and disadvantages of the logical model commonly used in databases? Is there any harvest after reading it? If you want to know more, welcome to the industry news!

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