sql - "INSERT INTO tab SELECT * FROM another_tab"的 UPSERT

Question

从另一个表中插入多行时，如何将“UPSERT”(插入或更新)插入到 SQLite 表中。

我试过:

INSERT INTO tab_name
SELECT * FROM tmp
ON CONFLICT(id)
    DO UPDATE SET
      val = excluded.val;

但它给了我:

syntax error near "DO"

实现该目标的正确且最有效的方法是什么？

Answer 1

您可能遇到了一个记录在案的名为 parsing ambiguity 的陷阱:

When the INSERT statement to which the UPSERT is attached takes its values from a SELECT statement, there is a potential parsing ambiguity. The parser might not be able to tell if the "ON" keyword is introducing the UPSERT or if it is the ON clause of a join. To work around this, the SELECT statement should always include a WHERE clause, even if that WHERE clause is just "WHERE true".)

那么，这样效果更好吗？

INSERT INTO tab_name
SELECT * FROM tmp WHERE true
ON CONFLICT(id) DO UPDATE SET val = excluded.val;