Snowflake masking and data types

Snowflake provides several functions to transform the data. This topic describes how Snowflake transforms the data for a given Protect masking type.

• Default masking: Snowflake does not support this masking type. Protect, however, uses the default masking type to apply protection to a wide range of data types. A default masking value is applied to each column according to the data type of the column.
  
Default masking values for data types

Column data type	Snowflake data type	Default masking value
NUMBER	NUMBER	0
DECIMAL	NUMBER	0
NUMERIC	NUMBER	0
INT	NUMBER	0
INTEGER	NUMBER	0
BIGINT	NUMBER	0
SMALLINT	NUMBER	0
TINYINT	NUMBER	0
BYTEINT	FLOAT	0
FLOAT	FLOAT	0
FLOAT4	FLOAT	0
FLOAT8	FLOAT	0
DOUBLE	FLOAT	0
DOUBLE PRECISION	FLOAT	0
REAL	FLOAT	0
VARCHAR	VARCHAR	*
CHAR	VARCHAR	*
CHARACTER	VARCHAR	*
STRING	VARCHAR	*
TEXT	VARCHAR	*
BINARY	BINARY	00
VARBINARY	BINARY	00
BOOLEAN	BOOLEAN	false
DATE	DATE	1970-01-01
DATETIME	TIMESTAMP_NTZ	1970-01-01 00:00:00.000
TIME	TIME	00:00:00
TIMESTAMP	TIMESTAMP_NTZ	1970-01-01 00:00:00.000
TIMESTAMP_LTZ	TIMESTAMP_LTZ	1969-12-31 16:00:00.000-0800 Note This may change depending on the time zone.
TIMESTAMP_NTZ	TIMESTAMP_NTZ	1970-01-01 00:00:00.000
TIMESTAMP_TZ	TIMESTAMP_TZ	1969-12-31 16:00:00.000-0800 Note This may change depending on the time zone.
VARIANT	VARIANT	0
OBJECT	OBJECT	{}
ARRAY	ARRAY	[]
GEOGRAPHY	GEOGRAPHY	{"coordinates": [0,0],"type": "Point"} (aka point(0, 0) and visualization can change based on user preferences)

• Hashing: Uses the following Snowflake functions:
  • SHA2 (for strings)
  • HASH (for numbers)
• Show last: Uses the following expressions:
  • substr(to_varchar(value), length(value) - n, n) (for strings)
  • mod(value, power(10,n)) (for numbers)
    Tip In the expressions, value indicates the content and n indicates the number of characters to be shown.
• No masking: Returns the raw content.