![]() In the context of relational databases, an upsert is a database operation that will update an existing row if a specified value already exists in a table, and insert a new row if the specified value doesn’t already exist. ON DUPLICATE KEY UPDATE syntax, mysqlaffectedrows() will return you 2 if the UPDATE was made (just as it does with the REPLACE. UPSERT in SQLite follows the syntax established by PostgreSQL, with generalizations. This makes using UPSERT a bit more straightforward than INSERT ON CONFLICT, since we don’t need to specify a conflict target or action. The term upsert is a portmanteau a combination of the words update and insert. UPSERT is a clause added to INSERT that causes the INSERT to behave as an UPDATE or a no-op if the INSERT would violate a uniqueness constraint. The UPSERT command in CockroachDB performs an upsert based on the uniqueness of the primary key column or columns, and it will perform an UPDATE or INSERT depending on whether the values being added are unique. I would like to insert the row if the column doesn't have the data already - regardless of the other columns. Let’s take a look at how they differ, and when we might want to use each. ![]() ![]() This requires the ip column to have a UNIQUE (or PRIMARY. While these two commands can achieve similar results, they’re not exactly the same. INSERT OR IGNORE INTO visits VALUES (ip, 0) UPDATE visits SET hits hits + 1 WHERE ip LIKE ip. UPSERT in CockroachDBĬockroachDB does have an UPSERT command, and like PostgreSQL, upserts can also be achieved using INSERT ON CONFLICT. Bulk INSERT of joined inheritance mappings requires that the ORM make use of the parameter internally, so that it can correlate primary key values from RETURNING rows from the base table into the parameter sets being used to INSERT into the sub table, which is why the SQLite backend illustrated. If we were to run this command with values that did not generate a conflict (for example, (5, ‘Kane’, it would insert a new row into employees with those values. In other words, the update takes precedence over the ignore. If you use both INSERT IGNORE and ON DUPLICATE KEY UPDATE in the same statement, the update will still happen if the insert finds a duplicate key. PostgreSQL detects a conflict – we’re trying to insert a row with an id value of 2, but a row with that id already exists in employees – so it runs UPDATE on that row using the new values. Essentially both commands are alternative-syntax versions of standard commands. This will insert a row, but if subject or text (or both) already exist, you instead update the existing row with given. Running this command would produce the same results as in Example #1 at the beginning of this article. INSERT INTO requests ('userid','subject','text','time') VALUES (56,'test','test 1234',6516516) ON DUPLICATE KEY UPDATE time VALUES (time), userid VALUES (userid) Have the relevant columns set to index UNIQUE.
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