![]() For this I am using this command: INSERT INTO zyprexa (NULL,'hello',0,0,0) SELECT date WHERE NOT EXISTS (SELECT 1 FROM zyprexa WHERE date'hello') so it should insert a row with the values null,'hello',0,0,0. The following code assumes that there is a primary key or unique constraint on the table to prevent the insertion of duplicate records. First you get the cursor count of table if any record found in the table mean it's return the cursor count 1 otherwise return zero.If cursor count one mean you perform UPDATE Operation otherwise Perform Insert Operation. I'm trying to do an insert into table if the table doesn't already contain a field with a specified value. If you go that route, when you call SubmitChanges, you have to take into account that either a) a SqlException could be raised for a duplicate insert, or b) you could have duplicate records in the table.įortunately, we can use the database to avoid the race condition by enforcing uniqueness. The - is a comment in SQL, and is equivalent to. Below we’ll examine the three different methods and explain the pros and cons of each in turn. If it doesnt exist, we execute our INSERT statement, and then return Record Added to our recordset. MySQL provides a number of useful statements when it is necessary to INSERT rows after determining whether that row is, in fact, new or already exists. for completeness lets do the routine thing of connections and cursors conn nnect (dbfile, timeout1000) cursor conn.cursor () get the count of. How to INSERT If Row Does Not Exist (UPSERT) in MySQL. just want to run a piece of code only IF the table doesn't exist). As others have pointed out, the if (!Any()) solutions all have a race condition. Wanted to share it here because I faced the same challenge as BrittonKerin and I managed to make it work (i.e.
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