One of those two outcomes must be guaranteed, regardless of concurrent activity, which has been called "the essential property of UPSERT".
Sqlite insert on conflict update#
"UPSERT" is a DBMS feature that allows a DML statement's author to atomically either insert a row, or on the basis of the row already existing, UPDATE that existing row instead, while safely giving little to no further thought to concurrency.
Sqlite insert on conflict Patch#
6.2 Miscellaneous odd properties of proposed ON CONFLICT patch.6 Challenges, issues (with ON CONFLICT patch).5.3.3.3 "Cardinality violation" errors in detail.5.3.3.2 Restrictions on query structure in detail.5.3.3 Overview of ON CONFLICT syntax itself.5.3 Syntax as proposed in the patch - INSERT.5.2.3 Teradata's Atomic UPSERT (UPDATE.5.2 Adopting an existing non-standard syntax.When ID=1 does not exist, the role will be set to 'Benchwarmer' instead of the default value. When ID=1 exists, the ROLE will be unaffected. INSERT OR REPLACE INTO Employee (id, role, name) When ID=1 does not exist, the name will be the default (NULL). When ID=1 exists, the NAME will be unaffected. GOOD but tedious: This will update 2 of the columns. UPSERT in SQLite follows the syntax established by PostgreSQL. UPSERT is a special syntax addition to INSERT that causes the INSERT to behave as an UPDATE or a no-op if the INSERT would violate a uniqueness constraint. UPSERT support in SQLite! UPSERT syntax was added to SQLite with version 3.24.0! the NAME column will be set to NULL or the default value: INSERT OR REPLACE INTO Employee (id, role) I think that the best way is to keep things on low level (db level) in order to keep a good level of performance.Īssuming three columns in the table: ID, NAME, ROLEīAD: This will insert or replace all columns with new values for ID=1: INSERT OR REPLACE INTO Employee (id, name, role)īAD: This will insert or replace 2 of the columns. Or maybe we can just try to find a solution 🙂 Some one has already thought about this problem and has a solution? If it fails because it can't find the row related to the record (it's not yet present in the db) it will try to do an insert UPDATE ON FAIL INSERT where it always try to do an update.ON CONFLICT UPDATE (this will only work when you have only 1 uniqueįields, if you have 2 or more unique fields that throw the conflict.To solve my problem I tought these solutions: If for a field it wont find the values ( I don't put it in the ContentValues ) it wont update those field but keep the old one (like a normal update query where you don't put a column for update it). I always do the insert, if it finds already a row with the same unique keys (conflict) it will only update the values. Instead I just discovered that the ON CONFLICT REPLACE if it finds a conflict it will do a delete->insert and if it can't find a value for a column (where I put null for not updating the field) it will replace the null value with the default column value in order to make successfully the insert.Īs you understand what I want to reach is this: Also I was thinking that in that insert (with the conflict) if I don't put a value for a column it wont do the replace but keep the old value. I started my project from the wrong concept that ON CONFLICT REPLACE will do an update of the row content when it finds a conflict.
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