Sql updating tables with foreign keys

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In other words, only values that are supposed to appear in the database are permitted.For example, say we have two tables, a CUSTOMER table that includes all customer data, and an ORDERS table that includes all customer orders.moreover, we looked at how SQL Create Table Primary Key and SQL Create table Foreign Key.

Along with this, we will discuss SQL Foreign Key with example and SQL create table Foreign Key.(tmp_table.tplname, tmp_table.source, tmp_table.domain together can be used to determine template.id).It might be a trivial question, but I'm quite new to SQL and not sure what the best query should be to populate the INSERT INTO translation (id, translated, language_id, template_id) SELECT tmp.id, tmp.translated, l.id, FROM tmp_table tmp JOIN language l USING (langname) JOIN template t USING (tplname, source, domain) ORDER BY clause that you don't strictly need, but certain queries may profit if you insert your data clustered that (or some other) way.I would like to update a foregin key value in table languages but it throws me error #1451 - Cannot delete or update a parent row: a foreign key constraint fails!SQL, we will see the definitions of Primary and Foreign Key in SQL.

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