The following demonstrates the supported syntax for data types supported in functions and procedures. Note that any data type supported by the driver is supported in a function or procedure. See "Data types" for more information on data types supported by the driver. 
BigInt |
Binary(ll)|
Boolean |
Char(ll)|
Date |
Decimal(pp, ss)|
Double |
Float |
GUID |
Integer |
JSON |
LongVarBinary(ll)|
LongVarChar(ll)|
NVarChar(ll)|
SmallInt |
Time((t))|
Timestamp((t))|
TinyInt|
VarBinary(ll)|
VarChar(ll)

where:

ll
is a value from 1 to 99 that specifies the length of the field.
pp
is a value from 1 to 99 that specifies the precision of the field.
ss
is a value from 1 to 99 that specifies the scale of the field.
t
is a value from 1 to 9 number of digits in the fractional seconds value of the field.