If you’re getting SQL Server error Msg 8117 with the message Operand data type varchar is invalid for sum operator, it’s because you’re passing the wrong data type to an operator or function.
In this case, the error indicates that we’re passing a string to the SUM() function. The SUM() function does not operate on strings. It only works on numeric types.
The same error (Msg 8117) can also occur in other contexts – it’s not limited to the SUM() function.
If you’re getting SQL Server error Msg 8116 with text that reads Argument data type date is invalid for argument 1 of substring function, it’s because you’re passing the wrong data type to a function – in this case, the SUBSTRING() function.
You could also see the same error (Msg 8116) in many other contexts – it’s not limited to the SUBSTRING() function.
If you’re getting SQL Server error Msg 8114 that reads something like Error converting data type varchar to numeric, it’s probably because you’re trying to perform a data type conversion that fails due to the value not being able to be converted to the destination type.
It’s not because you can’t convert that type to the new type. It’s because of the value itself.
If you’re receiving error Msg 8115, Level 16, Arithmetic overflow error converting int to data type numeric in SQL Server, it’s probably because you’re performing an operation that results in a data conversion error due to an out of range value.
This will often happen when you try to convert a number to a different data type, but it’s out of the accepted range for the new data type.
If you’re receiving error Msg 8115, Level 16, Arithmetic overflow error converting expression to data type int in SQL Server, it could be that you’re performing a calculation that results in an out of range value.
This can happen when you use a function such as SUM() on a column, and the calculation results in a value that’s outside the range of the column’s type.
If you’re getting error “Msg 8115, Level 16 Arithmetic overflow error converting IDENTITY to data type…” error in SQL Server, it’s probably because you’re trying to insert data into a table when its IDENTITY column has reached its data type’s limit.
An IDENTITY column automatically increments the value that’s inserted with each new row. If the value being inserted is out of the range of the column’s data type, then the above error will occur.
If you get error Msg 245 that reads “Conversion failed when converting the varchar value…” when trying to perform a concatenation operation in SQL Server, it’s likely that you’re attempting to concatenate a string and a number.
Doing this will result in an error, due to SQL Server trying to add the string and number instead of concatenate them.
To fix this, either convert the number to a string, or use a function like CONCAT() or CONCAT_WS() to perform the concatenation.
If you get the “operator does not exist: integer || integer” error in PostgreSQL, it’s probably because you’re trying to concatenate two numbers.
If you really want to concatenate two numbers, the easiest way to overcome this issue is to cast at least one of them to a string data type first.
Another way to do it is to use the CONCAT() function.
If you’re trying to back up the transaction logs in a SQL Server or SQL Edge database, but you get an error that states BACKUP LOG cannot be performed because there is no current database backup, you’ll need to perform at least one full backup of the database before you attempt to back up the transaction logs.
If you get an error that reads The statement BACKUP LOG is not allowed while the recovery model is SIMPLE when trying to back up a database in SQL Server or Azure SQL Edge, it’s because you’re trying to back up the transaction logs on a database that uses the simple recovery model.
To fix this, change the recovery model to either full or bulk logging.