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Editor to share with you what are the differences between hql and sql, I believe that most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

The difference between hql and sql in the database:

1. Sql is oriented to database table query.

2. Hql object-oriented query.

3. Hql: the class name followed by from + class object where is conditional on the attributes of the object.

4. Sql: from is followed by the table name where, followed by a conditional query using the fields in the table.

5. When using queries in Hibernate, Hql query statements are generally used.

6. HQL (Hibernate Query Language), that is, the query language of Hibernate is very similar to SQL. However, the most fundamental difference between HQL and SQL is that it is object-oriented.

When using queries in Hibernate, you typically use Hql query statements.

HQL (Hibernate Query Language), that is, the query language of Hibernate is very similar to SQL. However, the most fundamental difference between HQL and SQL is that it is object-oriented.

Note the following when using HQL:

Case sensitive

Because HQL is object-oriented, and the names and properties of object classes are case-sensitive, HQL is case-sensitive.

The HQL statement: from Cat as cat where cat.id > 1; is different from from Cat as cat where cat.ID > 1;, which is different from SQL.

From clause

From Cat, which returns an instance of a Cat object, which developers can also add an alias, eg. From Cat as cat. For more than one table query, please refer to the following:

From Cat as cat, Dog as dog

Other aspects are similar to SQL, so I won't repeat them here.

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