You can encrypt these datatypes:
int, smallint, tinyint
unsigned int, unsigned smallint, unsigned tinyint
bigint, unsigned bigint
decimal and numeric
float4 and float8
money, smallmoney
date, time, smalldatetime, datetime
char and varchar
unichar, univarchar
binary and varbinary
bit
Encrypted data on disk is stored in the varbinary datatype. See “Length of encrypted columns” for more information about the length of the varbinary data.
Null values are not encrypted.
