How to Efficiently Delete Rows Across Tables Using JOIN?

Cross-Table Data Deletion Using JOIN

When managing multiple tables, deleting rows across tables based on specific criteria can be a common task. In this case, let's explore how to efficiently remove all rows from a table (Table1) whose IDs match those in another table (Table2).

To achieve this, we can utilize a JOIN clause in the DELETE statement. The following query will accomplish the task:

DELETE t1
FROM Table1 t1
JOIN Table2 t2 ON t1.ID = t2.ID;

In this query:

• The DELETE statement initiates the deletion process.
• The FROM clause specifies the table (Table1) from which rows will be deleted.
• The JOIN clause establishes a relationship between Table1 and Table2 using the equality of the ID column in both tables.
• The t1 and t2 aliases are used to differentiate between the columns from the two tables.

By executing this query, all rows in Table1 that have IDs present in Table2 will be deleted. This is an effective method for performing cross-table data deletion without the need for subqueries or complex IN clauses.

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