join on followed by conditions in sql

The conditions of the JOIN ON clause in SQL are used to merge tables through comparison conditions between columns. The conditional syntax is: JOIN table2 ON table1.column = table2.column, where the columns must have compatible data types. If the connection type is not specified, INNER JOIN is used by default.

Conditions of JOIN ON clause in SQL

What is JOIN ON clause?

The JOIN ON clause is used to merge two or more tables in a SQL query. It specifies the conditions between the columns of the joined tables.

Conditional syntax

The conditional syntax of the JOIN ON clause is as follows:

JOIN table2 ON table1.column = table2.column

Among them:

• table1 and table2 are the two tables to be joined.
• column are the two columns to be compared.
• = is a comparison operator.

Conditional Examples

The following are some examples of JOIN ON clause conditions:

• JOIN orders ON customers. id = orders.customer_id
• JOIN products ON categories.id = products.category_id
• JOIN employees ON departments.id = employees.department_id

Note:

• The columns in the condition must have compatible data types.
• If no JOIN type is specified, INNER JOIN is used by default.
• You can use multiple JOIN ON clauses to join multiple tables.

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