This statement changes the error that MySQL throws when you use a normal INSERT statement into a warning so that the execution of your query isnât interrupted. The MySQL INSERT IGNORE statement is used to insert a new row and ignore execution errors causes by the statement. Without putting a constraint on the column that you want to be distinct, then MySQL will insert duplicate values just fine, and the following tutorials wonât work as intended. Keep in mind that before you create an insert row if not exists query, the MySQL table in use must already have one or more column(s) with PRIMARY KEY or UNIQUE constraint. Using the ON DUPLICATE KEY UPDATE clause.Values (getdate(), source.There are three ways you can perform an âinsert if not existsâ query in MySQL: On (target.ClockDate = source.ClockDate and target.UserName = source.UserName) Using (select as source (ClockDate, UserName) Take into consideration that I'm declaring variables what are likely stored procedure parameters (I suspect). In your case it would look similar to the following code. MERGE statement is a beautiful TSQL gem very well suited for "insert or update" situations. But before we begin, let us create a dummy dataset. INSERT INTO nameofthetable (columnname) SELECT FROM (SELECT valuename) AS val WHERE NOT EXISTS () In the nameofthetable we insert the valuename in the columnname if the conditional expression is met.I assume this based on the fact that you're using two where conditions in update statement later on in your code. The basic syntax for INSERT IF NOT EXISTS is as follows. In any case you cave too many closing braces. Inner select statement has only one where condition while UserName condition is excluded from the not exists due to invalid brace completion. Your code has a typo in your if statement in not exists(select.) part. So knowing how to logic it out as shown above is still a valid technique.Īs others have suggested that you should look into MERGE statement but nobody provided a solution using it I'm adding my own answer with this particular TSQL construct. However, in some cases, especially with large data sets, the merge statement can be prohibitively slow, causing a lot of tran log activity. WHERE clockDate = '' AND userName = 'test'Īs others have pointed out, the merge statement is another way to tackle this same logic. IF (NOT EXISTS(SELECT * FROM Clock WHERE clockDate = '') If clockDate is NOT datetime field (just date), then the SQL engine will do it for you - no need to cast on a set/insert statement. If you are trying to compare to a date (without the time) you need to cast or the time element will cause the compare to fail. Note that getdate gives you the current date. WHERE Cast(clockDate AS Date) = '' AND userName = 'test' I'm assuming that clockDate is a DateTime fields so try this: IF (NOT EXISTS(SELECT * FROM Clock WHERE cast(clockDate as date) = '') Is this a Visual Studio error or a SQL error? And I'll read up on Merge Statements, thank you both for the links.Īt first glance your original attempt seems pretty close. This is the result I want but this error confuses me. My table results are: clockDate userName clockIn breakOut breakIn clockOut WHERE (clockDate = GETDATE()) AND (userName = 'test') IF NOT EXISTS (SELECT * FROM Clock WHERE (clockDate = GETDATE()) AND (userName = 'test')) I hope I have explained this properly, and thank you for your so with the clockDate as a date field and breakOut as a time(0) field, should this work? Cause I'm still getting a "The Compound statement SQL construct or statement is not supported." Syntax error even though it seems to be working. IF EXISTS (SELECT query FROM mytable WHERE query'home') THEN UPDATE mytable SET query'home' AND keyword'home-link' WHERE query'home' ELSE INSERT INTO mytable (query, keyword) VALUES ('home', 'home-link') END IF IF EXISTS (SELECT query FROM mytable WHERE query'contact') THEN UPDATE mytable SET query'contact' AND keyword'contact-link. VALUES() AND userName = 'test')Īgain, this gives me the results I want, but not until after getting an error "Error in WHERE clause near 'CURRENT_DATE'. INSERT INTO Clock(clockDate, userName, breakOut) Here is what I tried: IF NOT EXISTS(SELECT * FROM Clock WHERE clockDate = '') AND userName = 'test') You could write a stored procedure to do this, or use a scripting language (bash, python, etc). The conditional syntax you tried is not supported. Where I'm stuck is if a user tries to clock out for break but never clocked in at the start of the shift, SQL needs to create a new row rather than update an existing. If you don't add a unique index to the query column, then you can't do an upsert using only SQL. I'm playing around with the SQL backend right now and have a question about compound statements. I'm extremely new to SQL and am trying to develop a time clock application for the small office that I work in. I apologize, but this is kind of a two part question.
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