There is boolean data type in SQL Server. Its values can be TRUE, FALSE or UNKNOWN. However, the boolean data type is only the result of a boolean expression containing some combination of comparison operators (e.g. =, <>, <, >=) or logical operators (e.g. AND, OR, IN, EXISTS).
Numeric datatype in TSQL: http://msdn.microsoft.com/en-us/library/ms187746.aspx According to the definition and article in the link above, Scale in a numeric datatype is the maximum number of decimal digits that can be stored to the right of the decimal point. Scale must be a value from 0 through p.
When you want to convert from float or real to character data, using the STR string function is usually more useful than CAST( ). This is because STR enables more control over formatting. For more information, see STR (Transact-SQL) and Functions (Transact-SQL).
The int data type is the primary integer data type in SQL Server. The bigint data type is intended for use when integer values might exceed the range that is supported by the int data type. bigint fits between smallmoney and int in the data type precedence chart.