In some scenarios like this one, SQL Server will silently truncate (N)VARCHAR values leading to serious data loss.
When data is inserted/update using an ORM, the definition usually incorporates a "max length" annotation/attribute that prevents this. However, when running in other contexts this is a serious issue?
Question: Can SQL Server be configured to not silently truncate VARCHAR values? (and issue an error/raise an exception instead)
The Database Engine has some built-in defaults for handling data types.
The definition of the data types
varchar is as follows:
char [ ( n ) ]Fixed-length, non-Unicode string data.
ndefines the string length and must be a value from 1 through 8,000. The storage size is
nbytes. The ISO synonym for char is character.
varchar [ ( n | max ) ]Variable-length, non-Unicode string data.
ndefines the string length and can be a value from 1 through 8,000.
maxindicates that the maximum storage size is 2^31-1 bytes (2 GB). The storage size is the actual length of the data entered + 2 bytes. The ISO synonyms for varchar are charvarying or charactervarying.
varchar the defaults are as follows:
nis not specified in a data definition or variable declaration statement, the default length is
nis not specified when using the CAST and CONVERT functions, the default length is
If you don't define a length, then SQL Server will do it for you.