SnowConvert AI - Redshift - Built-in functions¶
Bemerkung
For more information about built-in functions and their Snowflake equivalents, also see Common built-in functions.
Aggregatfunktionen¶
Aggregate functions compute a single result value from a set of input values. (Redshift SQL Language Reference Aggregate Functions).
Redshift |
Snowflake |
---|---|
ANY_VALUE ( [ DISTINCT |
ALL ] expression ) |
AVG ( [ DISTINCT | ALL ] expression ) |
AVG ( [ DISTINCT ] expression) Notes: Redshift and Snowflake may show different precision/decimals due to data type rounding/formatting. |
Notes: Redshift’s DISTINCT ignores trailing spaces (‚a ‚ = ‚a‘); Snowflake’s does not. (See SSC-FDM-PG0013). |
|
Notes: Snowflake does not allow the use of date types, while Redshift does. (See SSC-FDM-PG0013). |
|
STDDEV/STDDEV_SAMP ( [ DISTINCT |
ALL ] expression) STDDEV_POP ( [ DISTINCT |
VARIANCE/VAR_SAMP ( [ DISTINCT |
ALL ] expression) VAR_POP ( [ DISTINCT |
Array Functions¶
Creates an array of the SUPER data type. (Redshift SQL Language Reference Array Functions).
Redshift |
Snowflake |
---|---|
ARRAY ( [ expr1 ] [ , expr2 [ , … ] ] ) |
( [ <expr1> ] [ , <expr2> [ , … ] ] ) |
ARRAY_CONCAT ( super_expr1, super_expr2 ) |
ARRAY_CAT ( <array1> , <array2> ) |
( super_expr1,super_expr2,.. ) |
ARRAY_FLATTEN ( <array> ) Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
GET_ARRAY_LENGTH ( super_expr ) |
ARRAY_SIZE ( <array> | <variant>) |
SPLIT_TO_ARRAY ( string,delimiter ) |
SPLIT (<string>, <separator>) Notes: Redshift allows missing delimiters; Snowflake requires them, defaulting to comma |
SUBARRAY ( super_expr, start_position, length ) |
ARRAY_SLICE ( <array> , <from> , <to> ) Notes: Function names and the second argument differ; adjust arguments for equivalence. |
Conditional expressions¶
Redshift |
Snowflake |
---|---|
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
|
COALESCE ( expression, expression, … ) |
COALESCE ( expression, expression, … ) |
GREATEST ( value [, …] ) |
GREATEST_IGNORE_NULLS ( <expr1> [, <expr2> … ] ) |
LEAST ( value [, …] ) |
LEAST_IGNORE_NULLS ( <expr1> [, <expr2> … ]) |
NVL( expression, expression, … ) |
NVL ( expression, expression ) Notes: Redshift’s NVL accepts multiple arguments; Snowflake’s NVL accepts only two. To match Redshift behavior, NVL with more than two arguments is converted to COALESCE. |
Notes: Redshift’s NULLIF ignores trailing spaces in some string comparisons, unlike Snowflake. Therefore, the transformation adds RTRIM for equivalence. |
Data type formatting functions¶
Data type formatting functions provide an easy way to convert values from one data type to another. For each of these functions, the first argument is always the value to be formatted and the second argument contains the template for the new format. (Redshift SQL Language Reference Data type formatting functions).
Redshift |
Snowflake |
---|---|
Notes: Snowflake’s support for this function is partial (see SSC-EWI-0006). |
|
Notes: Snowflake’s |
Date and time functions¶
Redshift |
Snowflake |
---|---|
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
|
CONVERT_TIMEZONE ( <source_tz> , <target_tz> , <source_timestamp_ntz> ) CONVERT_TIMEZONE ( <target_tz> , <source_timestamp> ) Notes: Redshift defaults to UTC; the Snowflake function requires explicit UTC specification. Therefore, it will be added as the target timezone. |
|
DATEADD/DATE_ADD ( datepart, interval, {date | time | timetz | timestamp} ) |
DATE_ADD ( <date_or_time_part>, <value>, <date_or_time_expr> ) Notes: Invalid date part formats are translated to Snowflake-compatible formats. |
Notes: Invalid date part formats are translated to Snowflake-compatible formats. |
|
Notes: this function is partially supported by Snowflake. (See SSC-EWI-OOO6). |
|
DATE_PART_YEAR (date) |
YEAR ( <date_or_timestamp_expr> ) Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
Notes: Invalid date part formats are translated to Snowflake-compatible formats. |
|
GETDATE() |
GETDATE() |
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
|
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
|
SYSDATE() |
|
EXTRACT |
Bemerkung
Redshift timestamps default to microsecond precision (6 digits); Snowflake defaults to nanosecond precision (9 digits). Adjust precision as needed using ALTER SESSION (e.g., ALTER SESSION SET TIMESTAMP_OUTPUT_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF2';
). Precision loss may occur depending on the data type used.
Since some formats are incompatible with Snowflake, adjusting the account parameters DATE_INPUT_FORMAT or TIME_INPUT_FORMAT might maintain functional equivalence between platforms.
Hashfunktionen¶
A hash function is a mathematical function that converts a numerical input value into another value. (Redshift SQL Language Reference Hash functions).
Redshift |
Snowflake |
---|---|
FNV_HASH (value [, seed]) |
HASH ( <expr> [ , <expr> … ] |
JSON-Funktionen¶
Redshift |
Snowflake |
---|---|
Notes:
|
Math functions¶
Redshift |
Snowflake |
---|---|
DLOG10 (number) |
LOG (10, number) |
Bemerkung
Redshift and Snowflake results may differ in scale.
String functions¶
String functions process and manipulate character strings or expressions that evaluate to character strings. (Redshift SQL Language Reference String functions).
Redshift |
Snowflake |
---|---|
Notes: For negative lengths in |
|
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
|
QUOTE_IDENT (string) |
CONCAT (‚“‘, string, ‚“‘) |
Notes: This function includes a |
|
Notes: Certain special characters, the results may vary between platforms (See SSC-FDM-PG0013). |
|
Notes: Snowflake and Redshift handle SPLIT_PART differently with case-insensitive collations. |
|
STRPOS (string, substring ) |
POSITION ( <expr1> IN <expr> ) |
Notes: Snowflake partially supports this function. Redshift’s |
|
Notes: Redshift uses keywords (BOTH, LEADING, TRAILING) for trim; Snowflake uses TRIM, LTRIM, RTRIM. |
|
SUPER type information functions¶
Redshift |
Snowflake |
---|---|
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
|
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
Window functions¶
Redshift |
Snowflake |
---|---|
Notes: AVG rounding/formatting can vary by data type between Redshift and Snowflake. |
|
Notes: ORDER BY is mandatory in Snowflake; missing clauses are replaced with |
|
Notes: Snowflake needs ORDER BY; missing clauses get |
|
Notes: Snowflake needs ORDER BY; missing clauses get |
|
Notes: Redshift allows constant or expression offsets; Snowflake allows only constant offsets. |
|
Notes: Redshift’s DISTINCT ignores trailing spaces (‚a ‚ = ‚a‘); Snowflake’s does not. (See SSC-FDM-PG0013). |
|
Notes: Snowflake does not allow the use of date types, while Redshift does. (See SSC-FDM-PG0013). |
|
Notes: ORDER BY is mandatory in Snowflake; missing clauses are replaced with |
|
Notes: ORDER BY is mandatory in Snowflake; missing clauses are replaced with |
|
Notes: ORDER BY is mandatory in Snowflake; missing clauses are replaced with |
|
Notes: Rounding varies between platforms. |
|
Notes: the results may vary between platforms (See SSC-FDM-PG0013). |
|
Notes: ORDER BY is mandatory in Snowflake; missing clauses are replaced with |
|
STDDEV |
|
VARIANCE |
Bekannte Probleme ¶
For more information about quoted identifiers in functions, click here.
IDENTITY¶
Beschreibung ¶
Die Funktion IDENTITY ist eine Systemfunktion, die auf eine bestimmte Spalte einer Tabelle wirkt, um den Anfangswert für die Identität zu bestimmen. Wenn der Anfangswert nicht verfügbar ist, wird standardmäßig der in der Funktion angegebene Wert verwendet. Dies wird in eine Sequenz in Snowflake übersetzt.
Grammatikalische Syntax ¶
"identity"(oid_id, oid_table_id, default)
Bemerkung
Diese Funktion wird in Redshift nicht mehr unterstützt. Sie verwendet den Standardwert, um die Identität zu definieren und verhält sich wie eine Standard-Identitätsspalte.
Beispielhafte Quellcode-Muster¶
Eingabecode:¶
Redshift¶
CREATE TABLE IF NOT EXISTS table_test
(
id integer,
inventory_combo BIGINT DEFAULT "identity"(850178, 0, '5,3'::text)
);
INSERT INTO table_test (id) VALUES
(1),
(2),
(3),
(4);
SELECT * FROM table_test;
Results¶
id |
inventory_combo |
---|---|
1 |
5 |
2 |
8 |
3 |
11 |
3 |
14 |
Ausgabecode:
Snowflake¶
CREATE TABLE IF NOT EXISTS table_test
(
id integer,
inventory_combo BIGINT IDENTITY(5,3) ORDER
)
COMMENT = '{ "origin": "sf_sc", "name": "snowconvert", "version": { "major": 0, "minor": 0, "patch": "0" }, "attributes": { "component": "redshift", "convertedOn": "11/13/2024", "domain": "test" }}';
INSERT INTO table_test (id) VALUES
(1),
(2),
(3),
(4);
SELECT * FROM
table_test;
Results¶
id |
inventory_combo |
---|---|
1 |
5 |
2 |
8 |
3 |
11 |
3 |
14 |
Zugehörige EWIs¶
Es gibt keine bekannten Probleme.
TO_CHAR¶
Date function
Beschreibung¶
TO_CHAR konvertiert einen Zeitstempel oder numerischen Ausdruck in ein Zeichenfolgen-Datenformat. ([Redshift SQL-Referenz: TO_CHAR-Funktion](https://docs.aws.amazon.com/redshift/latest/dg/r_TO_CHAR. html))
Warnung
Diese Funktion wird in Snowflake teilweise unterstützt.
Weitere Informationen über zitierte Bezeichner in Funktionen finden Sie unter hier.
Grammatikalische Syntax¶
TO_CHAR(timestamp_expression | numeric_expression , 'format')
Beispielhafte Quellcode-Muster¶
Eingabecode:¶
Redshift¶
SELECT TO_CHAR(timestamp '2009-12-31 23:15:59', 'YYYY'),
TO_CHAR(timestamp '2009-12-31 23:15:59', 'YYY'),
TO_CHAR(timestamp '2009-12-31 23:15:59', 'TH'),
"to_char"(timestamp '2009-12-31 23:15:59', 'MON-DY-DD-YYYY HH12:MIPM'),
TO_CHAR(125.8, '999.99'),
"to_char"(125.8, '999.99');
Results¶
TO_CHAR |
TO_CHAR |
TO_CHAR |
TO_CHAR |
TO_CHAR |
---|---|---|---|---|
2009 |
009 |
DEC-THU-31-2009 11:15PM |
125,80 |
125,80 |
Ausgabecode:¶
Snowflake¶
SELECT
TO_CHAR(timestamp '2009-12-31 23:15:59', 'YYYY'),
PUBLIC.YEAR_PART_UDF(timestamp '2009-12-31 23:15:59', 3),
TO_CHAR(timestamp '2009-12-31 23:15:59', 'TH') !!!RESOLVE EWI!!! /*** SSC-EWI-0006 - TH FORMAT MAY FAIL OR MAY HAVE A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/!!!,
PUBLIC.MONTH_SHORT_UDF(timestamp '2009-12-31 23:15:59', 'uppercase') || '-' || PUBLIC.DAYNAME_SHORT_UDF(timestamp '2009-12-31 23:15:59', 'uppercase') || TO_CHAR(timestamp '2009-12-31 23:15:59', '-DD-YYYY HH12:MI') || PUBLIC.MERIDIAN_INDICATORS_UDF(timestamp '2009-12-31 23:15:59', 'uppercase'),
TO_CHAR(125.8, '999.99'),
TO_CHAR(125.8, '999.99');
Results¶
TO_CHAR |
TO_CHAR |
---|---|
2009 |
Dec-Thu-31-2009 11:15PM |
Bekannte Probleme ¶
Es wurden keine Probleme gefunden.
Zugehörige EWIs¶
SSC-EWI-0006: The current date/numeric format may have a different behavior in Snowflake.
Für Datetimes-Werte¶
Translation specification for the TO_CHAR function when transforming date or timestamp values to string
Beschreibung¶
Die folgenden Formatzeichenfolgen gelten für Funktionen wie TO_CHAR. Diese Zeichenfolgen können Datetime-Trennzeichen enthalten (z. B. „
-
“, „/
“, oder „:
“) und die folgenden „dateparts“ und „timeparts“. (Redshift-Referenzseite Datetime-Formatzeichenfolgen)
Grammatikalische Syntax¶
TO_CHAR (timestamp_expression, 'format')
In der folgenden Tabelle finden Sie die Zuordnung der einzelnen Formatelemente zu Snowflake:
Redshift |
Snowflake |
---|---|
|
|
|
|
|
|
|
Direkt unterstützt |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Notes: For this UDF to work correctly the Snowflake session parameter |
|
|
|
|
|
Direkt unterstützt |
|
|
|
Direkt unterstützt |
|
Direkt unterstützt |
|
Direkt unterstützt |
|
|
|
|
|
|
|
|
|
Notes: According to the redshift documentation, all timestamp with time zone are stored in UTC, which causes this format element to return a fixed result. |
|
+00 Notes: According to the redshift documentation, all timestamp with time zone are stored in UTC, which causes this format element to return a fixed result. |
|
|
|
Notes: This is a PostgreSQL template pattern modifier for „spell mode“, however it does nothing on Redshift, so it is removed from the output. |
|
Notes: This is another template pattern modifier for „fixed format“, however it has no use on the TO_CHAR function so it is removed. |
Beispielhafte Quellcode-Muster¶
Direkte Transformation von Formatelementen (keine Funktionen/UDFs)¶
Das Ergebnis wird als eine einzige TO_CHAR-Funktion erhalten
Redshift¶
Query¶
SELECT TO_CHAR('2013-10-03 13:50:15.456871'::TIMESTAMP, 'DD/MM/YY HH:MI:SS.MS') AS col1;
Result¶
+----------------------+
|col1 |
+----------------------+
|03/10/13 01:50:15.456 |
+----------------------+
Snowflake¶
Query¶
SELECT TO_CHAR('2013-10-03 13:50:15.456871'::TIMESTAMP, 'DD/MM/YY HH12:MI:SS.FF3') AS col1;
Result¶
+----------------------+
|col1 |
+----------------------+
|03/10/13 01:50:15.456 |
+----------------------+
Formattransformation mit Funktionen/UDFs¶
Das Ergebnis ist eine Verkettung mehrerer TO_CHAR, UDFs und integrierter Snowflake-Funktionen, die die entsprechende Zeichenfolgendarstellung des Werts für Datum und Uhrzeit erzeugen
Redshift¶
Query¶
SELECT TO_CHAR(DATE '2025-07-05', '"Today is " Month DAY DD, "it belongs to the week " IW') AS result;
Result¶
+-------------------------------------------------------------+
|result |
+-------------------------------------------------------------+
|Today is July SATURDAY 05, it belongs to the week 27 |
+-------------------------------------------------------------+
Snowflake¶
Query¶
SELECT
'Today is ' ||
TO_CHAR(DATE '2025-07-05', ' ') ||
PUBLIC.FULL_MONTH_NAME_UDF(DATE '2025-07-05', 'firstOnly') ||
' ' ||
PUBLIC.DAYNAME_LONG_UDF(DATE '2025-07-05', 'uppercase') ||
TO_CHAR(DATE '2025-07-05', ' DD, ') ||
'it belongs to the week ' ||
TO_CHAR(DATE '2025-07-05', ' ') ||
WEEKISO(DATE '2025-07-05') AS result;
Result¶
+-------------------------------------------------------------+
|result |
+-------------------------------------------------------------+
|Today is July SATURDAY 05, it belongs to the week 27 |
+-------------------------------------------------------------+
Zitierter Text¶
Formatelemente in doppelten Anführungszeichen werden direkt in die Ausgabe eingefügt, ohne dass sie interpretiert werden, doppelte Anführungszeichen mit Escapezeichen werden in ihr Snowflake-Äquivalent umgewandelt.
Redshift¶
Query¶
SELECT
TO_CHAR(DATE '2025-01-16', 'MM "TESTING DD" DD') AS result1,
TO_CHAR(DATE '2025-01-16', 'MM TESTING \\"DD\\" DD') AS result2,
TO_CHAR(DATE '2025-01-16', 'MM "TESTING \\"DD\\"" DD') AS result3;
Result¶
+-----------------+-------------------+-------------------+
|result1 |result2 |result3 |
+-----------------+-------------------+-------------------+
|01 TESTING DD 16 |01 TEST5NG "16" 16 |01 TESTING "DD" 16 |
+-----------------+-------------------+-------------------+
Snowflake¶
Query¶
SELECT
TO_CHAR(DATE '2025-01-16', 'MM ') || 'TESTING DD' || TO_CHAR(DATE '2025-01-16', ' DD') AS result1,
TO_CHAR(DATE '2025-01-16', 'MM TEST') || PUBLIC.ISO_YEAR_PART_UDF(DATE '2025-01-16', 1) || TO_CHAR(DATE '2025-01-16', 'NG ""DD"" DD') AS result2,
TO_CHAR(DATE '2025-01-16', 'MM ') || 'TESTING "DD"' || TO_CHAR(DATE '2025-01-16', ' DD') AS result3;
Result¶
+-----------------+-------------------+-------------------+
|result1 |result2 |result3 |
+-----------------+-------------------+-------------------+
|01 TESTING DD 16 |01 TEST5NG "16" 16 |01 TESTING "DD" 16 |
+-----------------+-------------------+-------------------+
Bekannte Probleme¶
Vorlagenmuster-Modifikatoren nicht unterstützt¶
Die folgenden Formatvorlagen-Modifikatoren:
FM (Füllmodus)
TH und th (Suffix der Ordnungszahl in Groß- und Kleinbuchstaben)
TM (Übersetzungsmodus)
Are not supported, including them in a format will generate SSC-EWI-0006
Eingabecode:
SELECT TO_CHAR(CURRENT_DATE, 'FMMonth'),
TO_CHAR(CURRENT_DATE, 'DDTH'),
TO_CHAR(CURRENT_DATE, 'DDth'),
TO_CHAR(CURRENT_DATE, 'TMMonth');
Ausgabecode:
SELECT
TO_CHAR(CURRENT_DATE(), 'FM') || PUBLIC.FULL_MONTH_NAME_UDF(CURRENT_DATE(), 'firstOnly') !!!RESOLVE EWI!!! /*** SSC-EWI-0006 - FMMonth FORMAT MAY FAIL OR MAY HAVE A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/!!!,
TO_CHAR(CURRENT_DATE(), 'DDTH') !!!RESOLVE EWI!!! /*** SSC-EWI-0006 - DDTH FORMAT MAY FAIL OR MAY HAVE A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/!!!,
TO_CHAR(CURRENT_DATE(), 'DDth') !!!RESOLVE EWI!!! /*** SSC-EWI-0006 - DDth FORMAT MAY FAIL OR MAY HAVE A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/!!!,
TO_CHAR(CURRENT_DATE(), 'TM') || PUBLIC.FULL_MONTH_NAME_UDF(CURRENT_DATE(), 'firstOnly') !!!RESOLVE EWI!!! /*** SSC-EWI-0006 - TMMonth FORMAT MAY FAIL OR MAY HAVE A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/!!!;
Parameter formatieren, der über die Variable übergeben wird
Wenn der Format-Parameter als Variable statt als String-Literal übergeben wird, kann die Transformation von Format-Elementen nicht angewandt werden. In den Verwendungen der Funktion wird eine FDM hinzugefügt, die darauf hinweist.
Eingabecode:
SELECT TO_CHAR(d, 'YYYY/MM/DD'),
TO_CHAR(d, f)
FROM (SELECT TO_DATE('2001-01-01','YYYY-MM-DD') as d, 'DD/MM/YYYY' as f);
Ausgabecode:
SELECT TO_CHAR(d, 'YYYY/MM/DD'),
--** SSC-FDM-0032 - PARAMETER 'format_string' IS NOT A LITERAL VALUE, TRANSFORMATION COULD NOT BE FULLY APPLIED **
TO_CHAR(d, f)
FROM (SELECT TO_DATE('2001-01-01','YYYY-MM-DD') as d, 'DD/MM/YYYY' as f);
Zugehörige EWIs¶
SSC-EWI-0006: The current date/numeric format may have a different behavior in Snowflake.
[SSC-FDM-0032](../../general/technical-documentation/issues-and-troubleshooting/functional-difference/generalFDM. md#ssc-fdm-0032): Parameter ist kein Literalwert, Transformation konnte nicht vollständig angewendet werden