I want to know how can I use UPSERT or in other words UPDATE if records exists Else enter new record operation in SQL Server using one statement? This example shows. And NOT EXISTS. Because I have read that EXISTS will work better than IN and NOT EXISTS will work better than NOT IN (read this is Oracle Ahh, but now there are 9. Ok, just tetsed, still works in 11g: Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production With the Partitioning option. ![]() These are the PL/SQL static SQL statements, which have the same syntax as the corresponding SQL statements, except as noted: SELECT (this statement is. A frequent occurrence when writing database procedures is to handle a scenario where given a set of fields, for example a new employee record, update the existing. If exists update else insert. A frequent occurrence when writing database procedures is to handle a scenario where given a set of fields, for example a new employee record, update the existing employee record if it exists otherwise create it. Often this problem is solved with a select statement and then an IF statement, eg: declare. It violates the mantra of performant database programming, which says: Do it in as few SQL queries as possible. There are two ways of solving the requirements that usually eliminate the extra select. Optimise For The Most Common. When coding a procedure, you should try and get an idea of how the procedure will be used. In this case, the question to ask whether the procedure will mostly be used to update existing employee records, or insert new ones. In this case, if it contain zero, it means the update failed to find any rows to update and therefore the record needs to be inserted instead. Use Merge. You can get away with even less code that this. Oracle 9i introduced the MERGE statement. The MERGE statement takes a list of records which are usually in a staging table, and adds them to a master table. If the record exists in the master table, it should be updated with the new values in the staging table, otherwise insert the record from the staging table. Sounds pretty similar the problem outlined above, except that merge wants the new records to be in a staging table. Luckily enough, we can fake a staging table using DUAL: create table employees (.
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