You can avoid that by explicitly stating all of the columns you want to retrieve from destination_old and perhaps using coalesce to retrieve the values from destination_old if the country field in source is null. I reached my objective in a little lengthy way by creating a work table where I inserted values of name1 and name2 by joining table1 on table2 then inserting subtraction into another column. Using the pattern above you end up with two country fields. I suspect that update statements with joins weren't included in SQLite because they're powerful but a bit risky. It's safe because you have a copy of destination before you altered it. I've been wrestling with this, and I know there are other options, but I've come to the conclusion the safest pattern is: create table destination_old as select * from destination įrom destination_old d left join source s ALTER TABLE RENAME The RENAME TO syntax changes the name of table-name to new-table-name. Syntax Following is the syntax of the UPDATE statement in SQLite UPDATE tablename SET column1 value1, column2 value2. The ALTER TABLE command in SQLite allows these alterations of an existing table: it can be renamed a column can be renamed a column can be added to it or a column can be dropped from it. To update specific rows, you need to use the WHERE clause along with it.
If you have data already present in both the tables and you want to update a table column values based on some condition then use this UPDATE Table1 set Name=(select t2.Name from Table2 t2 where t2.id=Table1.id) You can update the values of existing records in SQLite using the UPDATE statement. See SQL As Understood By SQLite: INSERT for a formal definition.
Solution 1 INSERT INTO Destination SELECT * FROM Source
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