![]() We use MySQL Update Join to update the column values of one main table with the new values of other tables related to the previous table using either INNER JOIN or LEFT JOIN on both table column values. Thus, the above syntax can be redesigned as the UPDATE JOIN syntax displayed above, and the query can be executed, and the desired result can be gained. The above UPDATE command works similarly to UPDATE JOIN with an implicit INNER JOIN or LEFT JOIN MySQL clauses. This is another way whose syntax can be written as:Ĭode: UPDATE Table1, Table2, SET Table1.ColB = Table2.ColB, Table2.ColC = Expression WHERE Table1.ColA = Table2.ColBAND Condition ![]() But in some cases, you may find the UPDATE query to alone perform the cross-table update without involving Joins. The work process is the same as explained in the syntax described above. Finally, you can put a Join condition using the WHERE clause to provide a limit records to records for updating. The expression denotes any expressional values or column fields mentioned in the update clause. Now, you will set the new values and assign them to both table columns, i.e., Table1 and Table2, that you want to modify. You can take any JOIN you want to apply from the two mentioned above, i.e., INNER JOIN or LEFT JOIN, together with a predicate of join. Secondly, we need to state the JOIN clause after the clause UPDATE. After the UPDATE clause, it is necessary to identify at least one table otherwise, if the table is not specified, then the data rows in the table will not be updated on the execution of the UPDATE query. SET Table1.ColB = Table2.ColB, Table2.ColC = ExpressionĮxplanation: Let us elaborate on the terms included in the above syntax structure:įirstly, take the main table (Table1) and another table (Table2), which joins the main table implemented after the UPDATE query. ![]() Hadoop, Data Science, Statistics & others UPDATE Table1, Table2, ![]()
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