Differential privacy SQL reference¶
This topic provides the following information:
- A reference for the SQL functions that are unique to differential privacy.
- A list of the Snowflake data types, operators, query syntax, and functions that are supported by differential privacy.
Differential privacy functions¶
The following functions are unique to differential privacy.
| Function | Description |
|---|---|
| DP_INTERVAL_LOW | Returns the lower bound of the noise interval. |
| DP_INTERVAL_HIGH | Returns the upper bound of the noise interval. |
Data types¶
The following data types are supported.
| Data type | Notes |
|---|---|
| BOOLEAN | |
| CHAR, CHARACTER | |
| DATE | |
| DATETIME | |
| DECIMAL, NUMERIC | |
| DOUBLE, DOUBLE PRECISION, REAL | |
| FLOAT, FLOAT4, FLOAT8 | |
| INT, INTEGER , BIGINT, SMALLINT, TINYINT, BYTEINT | |
| NUMBER | |
| STRING | |
| TEXT | |
| TIME | |
| TIMESTAMP, TIMESTAMP_NTZ | Time data types with time zones are not supported. Use TIMESTAMP or TIMESTAMP_NTZ. |
| VARCHAR |
Query syntax¶
The following elements of the Snowflake query syntax are supported.
| Syntax | Notes |
|---|---|
| SELECT | |
| SELECT ALL | |
| FROM | |
| INNER JOIN ON | See Supported joins. |
| INNER JOIN USING | See Supported joins. |
| LEFT OUTER JOIN ON | See Supported joins. |
| LEFT OUTER JOIN USING | See Supported joins. |
| RIGHT OUTER JOIN ON | See Supported joins. |
| RIGHT OUTER JOIN USING | See Supported joins. |
| FULL OUTER JOIN ON | See Supported joins. |
| FULL OUTER JOIN USING | See Supported joins. |
| NATURAL JOIN | See Supported joins. |
| WHERE | |
| GROUP BY | Aliases are not supported in the GROUP BY clause. For example, GROUP BY col_a AS column_a is not supported. |
- Limitations on query syntax
Quoted identifiers (for example, column, table, schema and database names) are not supported.
Operators¶
Arithmetic operators¶
The following arithmetic operators are supported.
| Operator | Notes |
|---|---|
- (unary) | |
- | |
+ (unary) | Does not work with strings. |
+ | |
* | |
/ | |
% |
Comparison operators¶
The following comparison operators are supported.
| Operator | Notes |
|---|---|
= | |
!= | |
< | |
> | |
<= | |
>= |
Logical operators¶
The following logical operators are supported.
| Operator | Notes |
|---|---|
| AND | |
| NOT | |
| OR |
Set operators¶
The following set operators are supported.
| Operator | Notes |
|---|---|
| UNION [ ALL ] |
Subquery operators¶
Subquery operators are not supported.
Functions¶
Aggregate functions¶
The following aggregate functions are supported.
| Function | Notes |
|---|---|
| ANY_VALUE | Supported only as an aggregate for a subquery with a GROUP BY clause. |
| COUNT | |
| COUNT DISTINCT |
Bitwise expression functions¶
Bitwise expression functions are not supported.
Conditional expression functions¶
The following conditional expression functions are supported.
| Function | Notes |
|---|---|
| [ NOT ] IN | |
| CASE | |
| COALESCE | |
| DECODE | |
| EQUAL_NULL | |
| GREATEST | |
| IFF | |
| IS [NOT] NULL | |
| LEAST |
Context functions¶
Context functions are not supported.
Conversion functions¶
The following conversion functions are supported.
| Function | Notes |
|---|---|
CAST, :: | Columns must be explicitly non-null to be casted. To do this, filter out nulls before casting. Casting other data types to STRING is not supported. |
| TO_BOOLEAN | |
| TO_CHAR , TO_VARCHAR | |
| TO_DECIMAL , TO_NUMBER , TO_NUMERIC | |
| TO_DOUBLE | |
| TRY_CAST | |
| TRY_TO_BOOLEAN | |
| TRY_TO_DECIMAL, TRY_TO_NUMBER, TRY_TO_NUMERIC | |
| TRY_TO_DOUBLE |
Data generation functions¶
Data generation functions are not supported.
Data metric functions¶
Data metric functions are not supported. User-defined DMFs are also not supported.
Date & time functions¶
The following date & time functions are supported.
| Function | Notes |
|---|---|
| DATE_PART | The following date and time parts are not supported: dayofweek, week, yearofweek, nanosecond, epoch_*, and timezone_*. |
| DAYNAME | |
| EXTRACT | The following date and time parts are not supported: dayofweek, week, yearofweek, nanosecond, epoch_*, and timezone_*. |
| HOUR | |
| LAST_DAY | |
| MINUTE | |
| SECOND | |
| TRUNC | |
| YEAR* / DAY* / WEEK* / MONTH / QUARTER |
Encryption functions¶
Encryption functions are not supported.
File functions¶
File functions are not supported.
Geospatial functions¶
Geospatial functions are not supported.
Hash functions¶
Hash functions are not supported.
Metadata functions¶
Metadata functions are not supported.
Numeric functions¶
The following numeric functions are supported.
| Function | Notes |
|---|---|
| ABS | |
| CEIL | |
| FLOOR | |
| MOD | |
| SIGN |
Regular expression functions¶
Regular expression functions are not supported.
Semi-structured and structured data functions¶
Semi-structured and structured data functions are not supported.
String and binary functions¶
The following string & binary functions are supported.
| Function | Notes |
|---|---|
| CONTAINS | |
| LENGTH , LEN | |
| LOWER | |
| POSITION | |
| UPPER |
System functions¶
System functions are not supported.
Table functions¶
Table functions are not supported.