The operator to concatenate in SQL Server is '+', but this operator is also used to add values.

Being the same operator for both, the query analyzer makes a concatenation or a sum based on the type of data fields being treated. If the fields are of 'string' type, the operator concatenate, and if it has numeric fields, two integers, for example, it add the two values.

In many cases, especially in ETL processes or data loading to a data warehouse, for example, we would rather use a single sentence or the checking of the existence of a register and its updating. If register doesn't exist we would want to insert it. This combination has been nicknamed UPSERT, although in SQL there is a specific statement to make it, which is MERGE.

Con los nuevos tiempos surgen nuevas profesiones, o nuevas maneras de orientar profesiones ya existentes, y con la llegada de los Big Data la figura del analista de la información 'se reinventa', como dicen ahora, para convertirse en Experto en Big Data, que por lo que parece puede llegar a estar muy bien reconocido según esta infografía de FICO..