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The editor will share with you how many basic operations of relationships are in the relational database. I hope you will gain something after reading this article. Let's discuss it together.

In a relational database, find tuples that meet a given condition from a relationship. This operation is called: select. The conditions are given in logical expressions, and tuples with true values are selected.

The operation of finding tuples from a relationship that meets a given condition is called selection. The conditions are given in logical expressions, and tuples with true values are selected.

This operation extracts tuples from the horizontal direction. The phrases FOR and WHILE in FOXPRO are equivalent to selection operations.

In a relational database, there are three basic operations of relationships, which are:

1. Select operation: the operation of finding tuples that meet a given condition from a relationship

2. Projection operation: the operation of selecting several attributes from a relationship to form a new relationship.

3. Join operation: the operation of merging two or more relationships into a new relationship according to the associated field.

After reading this article, I believe you have a certain understanding of "how many basic operations of relationships in relational databases". If you want to know more about it, you are welcome to follow the industry information channel. Thank you for reading!

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