![]() HINT: For debugging reasons, you may comment out the "-select raise(ignore)" line. Īdditionally, everything contained within the trigger will also consider updates performed recently, by the code itself (unlike a global update which first prepares the set to update and then executes, without considering the results of its proper update. I've looked at sqlite trigger examples and I can't see my error. For example, if I say UPDATE 'names' SET name'foo' where id1 then the value of 'len' becomes 3 for all rows of the table. You will notice that this trick is extremely fast, much faster than update with a where clause. The update trigger writes the new length to all rows of the table, despite the WHERE clause. Update real_table set val1 = new.val1, val2 = new.val2 where id = new.id Here is the code example: drop table if exists dummy Ĭreate temporary table dummy (id number, val1, val2) Ĭreate trigger dummy_ins before insert on dummy SQLite insert data The INSERT statement is used to insert data into tables. These statements are part of the SQL Data Manipulation Language (DML). ![]() We will use the INSERT, DELETE, and UPDATE statements. Instead of updating real_table, INSERT into DUMMY. In this part of the SQLite tutorial, we will insert, update and delete data from SQLite tables. I want to update and select one row within one query in SqLite. Then formulate your query, however complex, containing joins, aggregates, withs. Table 1 has 50,000 rows and Table 2 has 25 million rows. ![]() Here's a TRICK for complex updates: use a trigger on a dummy temporary table which never receives any records. ![]()
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