Kundenspezifische UDFs in SnowConvert¶

     --Create Table
     CREATE TABLE bfile_table ( col1 BFILE );
 
     --Insert Bfilename
     INSERT INTO bfile_table VALUES ( BFILENAME('mydirectory', 'myfile.png') );

     --Select
     SELECT * FROM bfile_table;

--Create Table
CREATE OR REPLACE TABLE bfile_table ( col1
!!!RESOLVE EWI!!! /*** SSC-EWI-OR0105 - ADDITIONAL WORK IS NEEDED FOR BFILE COLUMN USAGE. BUILD_STAGE_FILE_URL FUNCTION IS A RECOMMENDED WORKAROUND ***/!!!
VARCHAR
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;

--Insert Bfilename
INSERT INTO bfile_table
VALUES (PUBLIC.BFILENAME_UDF('mydirectory', 'myfile.png') );

--Select
SELECT * FROM
bfile_table;

 :force: 

 --Create Table
CREATE TABLE jsdateudf_table( col1 DATE );

--Create Procedure
CREATE OR REPLACE PROCEDURE jsdateudf_proc ( par1 DATE )
IS
BEGIN
    INSERT INTO jsdateudf_table VALUES(par1);
END;

--Insert Date
CALL jsdateudf_proc('20-03-1996');

--Select
SELECT * FROM jsdateudf_table;

 --Create Table
CREATE OR REPLACE TABLE jsdateudf_table ( col1 TIMESTAMP /*** SSC-FDM-OR0042 - DATE TYPE COLUMN HAS A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;

--Create Procedure
CREATE OR REPLACE PROCEDURE jsdateudf_proc (par1 TIMESTAMP /*** SSC-FDM-OR0042 - DATE TYPE COLUMN HAS A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/)
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$
    BEGIN
        INSERT INTO jsdateudf_table
        VALUES(:par1);
    END;
$$;

--Insert Date
CALL jsdateudf_proc('20-03-1996');

--Select
SELECT * FROM
    jsdateudf_table;

 --Create Table
CREATE TABLE datetojulian_table (col1 DATE);

INSERT INTO datetojulian_table VALUES (DATE '2020-01-01');
INSERT INTO datetojulian_table VALUES (DATE '1900-12-31');
INSERT INTO datetojulian_table VALUES (DATE '1904-02-29');
INSERT INTO datetojulian_table VALUES (DATE '1903-03-01');
INSERT INTO datetojulian_table VALUES (DATE '2000-12-31');

--Select
SELECT TO_CHAR(col1, 'J') FROM datetojulian_table;

 --Create Table
CREATE OR REPLACE TABLE datetojulian_table (col1 TIMESTAMP /*** SSC-FDM-OR0042 - DATE TYPE COLUMN HAS A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;

INSERT INTO datetojulian_table
VALUES (DATE '2020-01-01');

INSERT INTO datetojulian_table
VALUES (DATE '1900-12-31');

INSERT INTO datetojulian_table
VALUES (DATE '1904-02-29');

INSERT INTO datetojulian_table
VALUES (DATE '1903-03-01');

INSERT INTO datetojulian_table
VALUES (DATE '2000-12-31');

--Select
SELECT
PUBLIC.DATE_TO_JULIAN_DAYS_UDF(col1)
FROM
datetojulian_table;

 SELECT
    TO_TIMESTAMP('03/08/2009, 12:47 AM', 'dd/mm/yy, hh:mi AM')+62.40750856543442
FROM DUAL;

 SELECT
    PUBLIC.DATEADD_UDF(TO_TIMESTAMP('03/08/2009, 12:47 AM', 'dd/mm/yy, hh:mi AM'), 62.40750856543442)
FROM DUAL;

 --Create Table
CREATE TABLE times(AsTimeStamp TIMESTAMP, AsDate DATE);

--Subtraction operations
SELECT AsDate - unknown FROM times, unknown_table;
SELECT unknown - AsTimeStamp FROM times;
SELECT AsTimeStamp - unknown FROM times;
SELECT unknown - AsDate FROM times;

 --Create Table
CREATE OR REPLACE TABLE times (AsTimeStamp TIMESTAMP(6),
AsDate TIMESTAMP /*** SSC-FDM-OR0042 - DATE TYPE COLUMN HAS A DIFFERENT BEHAVIOR IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
;

--Subtraction operations
SELECT
PUBLIC.DATEDIFF_UDF(
                     !!!RESOLVE EWI!!! /*** SSC-EWI-OR0036 - TYPES RESOLUTION ISSUES, ARITHMETIC OPERATION '-' MAY NOT BEHAVE CORRECTLY BETWEEN DATE AND unknown ***/!!!
 AsDate, unknown) FROM
times,
unknown_table;

SELECT
PUBLIC.DATEDIFF_UDF(
                     !!!RESOLVE EWI!!! /*** SSC-EWI-OR0036 - TYPES RESOLUTION ISSUES, ARITHMETIC OPERATION '-' MAY NOT BEHAVE CORRECTLY BETWEEN unknown AND Timestamp ***/!!!
 unknown, AsTimeStamp) FROM
times;

SELECT
PUBLIC.DATEDIFF_UDF(
                     !!!RESOLVE EWI!!! /*** SSC-EWI-OR0036 - TYPES RESOLUTION ISSUES, ARITHMETIC OPERATION '-' MAY NOT BEHAVE CORRECTLY BETWEEN Timestamp AND unknown ***/!!!
 AsTimeStamp, unknown) FROM
times;

SELECT
PUBLIC.DATEDIFF_UDF(
                     !!!RESOLVE EWI!!! /*** SSC-EWI-OR0036 - TYPES RESOLUTION ISSUES, ARITHMETIC OPERATION '-' MAY NOT BEHAVE CORRECTLY BETWEEN unknown AND DATE ***/!!!
 unknown, AsDate) FROM
times;

 -- CREATE TABLE UNKNOWN_TABLE(Unknown timestamp);
-- INSERT  INTO UNKNOWN_TABLE VALUES (TO_TIMESTAMP('01/10/09, 12:00 P.M.', 'dd/mm/yy, hh:mi P.M.'));

CREATE TABLE TIMES(AsTimeStamp TIMESTAMP);
INSERT INTO TIMES VALUES (TO_TIMESTAMP('05/11/21, 11:00 A.M.', 'dd/mm/yy, hh:mi A.M.'));

SELECT AsTimeStamp - unknown FROM times, unknown_table;

|ASTIMESTAMP-UNKNOWN|
|-------------------|
|4417 23:0:0.0      |

 -- CREATE TABLE UNKNOWN_TABLE(Unknown timestamp);
-- INSERT INTO UNKNOWN_TABLE VALUES (TO_TIMESTAMP('01/10/09, 12:00 P.M.', 'dd/mm/yy, hh:mi P.M.'));
CREATE OR REPLACE TABLE TIMES (AsTimeStamp TIMESTAMP(6)
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;

INSERT INTO TIMES
VALUES (TO_TIMESTAMP('05/11/21, 11:00 A.M.', 'dd/mm/yy, hh:mi A.M.'));

SELECT
PUBLIC.DATEDIFF_UDF(
    !!!RESOLVE EWI!!! /*** SSC-EWI-OR0036 - TYPES RESOLUTION ISSUES, ARITHMETIC OPERATION '-' MAY NOT BEHAVE CORRECTLY BETWEEN Timestamp AND unknown ***/!!!
    AsTimeStamp,
    unknown
)
FROM
times,
unknown_table;

PUBLIC.DATEDIFF_UDF( ASTIMESTAMP, UNKNOWN)|
------------------------------------------+
                                      4418|

 CREATE TABLE MY_TAB (
    my_json VARCHAR(5000)
);

INSERT INTO MY_TAB VALUES ('{ 
    "store": {
      "book": [ 
        { "category": "reference",
          "author": "Nigel Rees",
          "title": "Sayings of the Century",
          "price": 8.95
        },
        { "category": "fiction",
          "author": "Evelyn Waugh",
          "title": "Sword of Honour",
          "price": 12.99
        },
        { "category": "fiction",
          "author": "Herman Melville",
          "title": "Moby Dick",
          "isbn": "0-553-21311-3",
          "price": 8.99
        },
        { "category": "fiction",
          "author": "J. R. R. Tolkien",
          "title": "The Lord of the Rings",
          "isbn": "0-395-19395-8",
          "price": 22.99
        }
      ],
      "bicycle": {
        "color": "red",
        "price": 19.95
      }
    }
  }');

 CREATE OR REPLACE TABLE MY_TAB (
       my_json VARCHAR(5000)
   )
   COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
   ;

   INSERT INTO MY_TAB
   VALUES ('{ 
    "store": {
      "book": [ 
        { "category": "reference",
          "author": "Nigel Rees",
          "title": "Sayings of the Century",
          "price": 8.95
        },
        { "category": "fiction",
          "author": "Evelyn Waugh",
          "title": "Sword of Honour",
          "price": 12.99
        },
        { "category": "fiction",
          "author": "Herman Melville",
          "title": "Moby Dick",
          "isbn": "0-553-21311-3",
          "price": 8.99
        },
        { "category": "fiction",
          "author": "J. R. R. Tolkien",
          "title": "The Lord of the Rings",
          "isbn": "0-395-19395-8",
          "price": 22.99
        }
      ],
      "bicycle": {
        "color": "red",
        "price": 19.95
      }
    }
  }');

 -- 'Sayings of the Century'
SELECT JSON_VALUE(MY_JSON, '$..book[0].title') AS VALUE FROM MY_TAB;

-- NULL
-- gets books in positions 0, 1, 2 and 3 but returns null (default behavior) since a non scalar value was returned
SELECT JSON_VALUE(MY_JSON, '$..book[0,1 to 3,3]') AS VALUE FROM MY_TAB;

-- 'Sayings of the Century'
SELECT JSON_VALUE(MY_JSON, '$.store.book[*]?(@.category == "reference").title') AS VALUE FROM MY_TAB;

-- 'MY ERROR MESSAGE'
-- triggers error because the result is a non scalar value (is an object)
SELECT JSON_VALUE(MY_JSON, '$..book[0]' DEFAULT 'MY ERROR MESSAGE' ON ERROR DEFAULT 'MY EMPTY MESSAGE' ON EMPTY) AS VALUE FROM MY_TAB;

-- 'MY EMPTY MESSAGE'
-- triggers the on empty class because does not exists in the first book element
SELECT JSON_VALUE(MY_JSON, '$..book[0].isbn' DEFAULT 'MY ERROR MESSAGE' ON ERROR DEFAULT 'MY EMPTY MESSAGE' ON EMPTY) AS VALUE FROM MY_TAB;

-- Oracle error message: ORA-40462: JSON_VALUE evaluated to no value
-- this is a custom message from the UDF when no match is found and the ON ERROR clause is set to ERROR
SELECT JSON_VALUE(MY_JSON, '$..book[0].isbn' ERROR ON ERROR) AS VALUE FROM MY_TAB;

-- NULL
SELECT JSON_VALUE(MY_JSON, '$..book[0].isbn' NULL ON ERROR) AS VALUE FROM MY_TAB;

-- Oracle error message: ORA-40462: JSON_VALUE evaluated to no value
-- this is a custom message from the UDF when no match is found and the ON EMPTY clause is set to ERROR
SELECT JSON_VALUE(MY_JSON, '$..book[0].isbn' ERROR ON EMPTY) AS VALUE FROM MY_TAB;

-- NULL
SELECT JSON_VALUE(MY_JSON, '$..book[0].isbn' NULL ON EMPTY) AS VALUE FROM MY_TAB;

-- 'Sayings of the Century'
SELECT JSON_VALUE(MY_JSON, '$..book[0].title' RETURNING VARCHAR2) AS VALUE FROM MY_TAB;

-- 'Sayin'
SELECT JSON_VALUE(MY_JSON, '$..book[0].title' RETURNING VARCHAR2(5) TRUNCATE) AS VALUE FROM MY_TAB;

-- 'Sayings of the Century'
SELECT JSON_VALUE(MY_JSON, '$..book[0].title' RETURNING CLOB) AS VALUE FROM MY_TAB;

-- NULL
-- This is because the title field is a string and the function expects a number result type
SELECT JSON_VALUE(MY_JSON, '$..book[0].title' RETURNING NUMBER) AS VALUE FROM MY_TAB;

-- 420
-- This is because the title field is a string and the function expects a number result type
SELECT JSON_VALUE(MY_JSON, '$..book[0].title' RETURNING NUMBER DEFAULT 420 ON ERROR) AS VALUE FROM MY_TAB;

-- Oracle error message: ORA-01858: a non-numeric character was found where a numeric was expected
SELECT JSON_VALUE(MY_JSON, '$..book[0].title' RETURNING DATE ERROR ON ERROR) AS VALUE FROM MY_TAB;

-- ORA-40450: invalid ON ERROR clause
SELECT JSON_VALUE(MY_JSON, '$..book[0].title' ERROR ON MISMATCH) AS VALUE FROM MY_TAB;

-- 'Sayings of the Century'
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].title', NULL, NULL, NULL) AS VALUE FROM
MY_TAB;

-- NULL
-- gets books in positions 0, 1, 2 and 3 but returns null (default behavior) since a non scalar value was returned
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0,1 to 3,3]', NULL, NULL, NULL) AS VALUE FROM
MY_TAB;

-- 'Sayings of the Century'
SELECT
JSON_VALUE_UDF(MY_JSON, '$.store.book[*]?(@.category == "reference").title', NULL, NULL, NULL) AS VALUE FROM
MY_TAB;

-- 'MY ERROR MESSAGE'
-- triggers error because the result is a non scalar value (is an object)
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0]', NULL, 'MY ERROR MESSAGE' :: VARIANT, 'MY EMPTY MESSAGE' :: VARIANT) AS VALUE FROM
MY_TAB;

-- 'MY EMPTY MESSAGE'
-- triggers the on empty class because does not exists in the first book element
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].isbn', NULL, 'MY ERROR MESSAGE' :: VARIANT, 'MY EMPTY MESSAGE' :: VARIANT) AS VALUE FROM
MY_TAB;

-- Oracle error message: ORA-40462: JSON_VALUE evaluated to no value
-- this is a custom message from the UDF when no match is found and the ON ERROR clause is set to ERROR
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].isbn', NULL, 'SSC_ERROR_ON_ERROR' :: VARIANT, NULL) AS VALUE FROM
MY_TAB;

-- NULL
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].isbn', NULL, 'SSC_NULL_ON_ERROR' :: VARIANT, NULL) AS VALUE FROM
MY_TAB;

-- Oracle error message: ORA-40462: JSON_VALUE evaluated to no value
-- this is a custom message from the UDF when no match is found and the ON EMPTY clause is set to ERROR
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].isbn', NULL, NULL, 'SSC_ERROR_ON_EMPTY' :: VARIANT) AS VALUE FROM
MY_TAB;

-- NULL
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].isbn', NULL, NULL, 'SSC_NULL_ON_EMPTY' :: VARIANT) AS VALUE FROM
MY_TAB;

-- 'Sayings of the Century'
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].title', 'string', NULL, NULL) AS VALUE FROM
MY_TAB;

-- 'Sayin'
SELECT
LEFT(JSON_VALUE_UDF(MY_JSON, '$..book[0].title', 'string', NULL, NULL), 5) AS VALUE FROM
MY_TAB;

-- 'Sayings of the Century'
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].title', 'string', NULL, NULL) AS VALUE FROM
MY_TAB;

-- NULL
-- This is because the title field is a string and the function expects a number result type
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].title', 'number', NULL, NULL) AS VALUE FROM
MY_TAB;

-- 420
-- This is because the title field is a string and the function expects a number result type
SELECT
JSON_VALUE_UDF(MY_JSON, '$..book[0].title', 'number', 420 :: VARIANT, NULL) AS VALUE FROM
MY_TAB;

-- Oracle error message: ORA-01858: a non-numeric character was found where a numeric was expected
SELECT
!!!RESOLVE EWI!!! /*** SSC-EWI-0021 - RETURNING CLAUSE NOT SUPPORTED IN SNOWFLAKE ***/!!!
JSON_VALUE_UDF(MY_JSON, '$..book[0].title', NULL, 'SSC_ERROR_ON_ERROR' :: VARIANT, NULL) AS VALUE FROM
MY_TAB;

-- ORA-40450: invalid ON ERROR clause
SELECT
!!!RESOLVE EWI!!! /*** SSC-EWI-0021 - ON MISMATCH CLAUSE NOT SUPPORTED IN SNOWFLAKE ***/!!!
JSON_VALUE_UDF(MY_JSON, '$..book[0].title', NULL, NULL, NULL) AS VALUE FROM
MY_TAB;

 CREATE OR REPLACE FUNCTION PUBLIC.JULIAN_TO_GREGORIAN_DATE_UDF(JULIAN_DATE CHAR(7), FORMAT_SELECTED CHAR(1))
RETURNS variant
LANGUAGE JAVASCRIPT
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"udf"}}'
AS
$$
    const CONST_FOR_MODIFIED_JULIAN_DATE = 0.5;
    const BEGINNING_OF_GREG_CALENTAR = 2299161;
    const CONST_AFTER_GREG_VALUE = 1867216.25;
    const DIVIDENT_TO_GET_CENTURY = 36524.25;
    const LEAP_YEAR_CONSTANT = 4;
    const CONST_TO_GET_DAY_OF_MONTH = 30.6001;

    //Functions definitions

    function julianToGregorian(julianDate){
        const JD = julianDate + CONST_FOR_MODIFIED_JULIAN_DATE; //setting modified julian date 
        const Z = Math.floor(JD); //setting fractional part of julian day
        const F = JD - Z; //fractional part of the julian date
        let A, alpha, B, C, D, E, year, month, day;
        
        //verification for the beginning of gregorian calendar
        if(Z < BEGINNING_OF_GREG_CALENTAR){ 
            A=Z; 
        } else {
            //alpha is for dates after the beginning of gregorian calendar
            alpha = Math.floor((Z-CONST_AFTER_GREG_VALUE) / DIVIDENT_TO_GET_CENTURY);
            A=Z+1+alpha - Math.floor(alpha/LEAP_YEAR_CONSTANT);
        }

        B = A + 1524;
        C = Math.floor((B-122.1)/365.25);
        D = Math.floor(365.25*C);
        E = Math.floor((B-D)/CONST_TO_GET_DAY_OF_MONTH);

        day= Math.floor(B-D-Math.floor(CONST_TO_GET_DAY_OF_MONTH*E)+F);
        month=(E<14)? E -1: E-13;
        year=(month>2)? C-4716: C-4715;

        return new Date(year, month-1, day);
    }

function cyydddToGregorian(julianDate){
        var c=Math.floor(julianDate/1000);
        var yy=(c<80)? c+2000: c+1900;
        var ddd=julianDate%1000;
        var date= new Date(yy, 0);
        date.setDate(ddd);
        return date;
    }

function ordinalDate(ordinalDate){
    const year = parseInt(ordinalDate.toString().substring(0,4));
    const dayOfYear = parseInt(ordinalDate.toString().substring(4));
    const date = new Date(year, 0); //Set date to the first day of year
    date.setDate(dayOfYear);
    return date;
}

function formatDate(toFormatDate){
    toFormatDate = toFormatDate.toDateString();
    let year = toFormatDate.split(" ")[3];
    let month = toFormatDate.split(" ")[1];
    let day = toFormatDate.split(" ")[2];
    return new Date(month + day + ", " + Math.abs(year)).toISOString().split('T')[0]
}

    switch(FORMAT_SELECTED){
        case 'E': 
            //JD Edwards World formar, century added  - CYYDDD
            var result = formatDate(cyydddToGregorian(parseInt(JULIAN_DATE)));
            return result;
        break; 
        case 'J':
            //astronomical format YYYYDDD
            return formatDate(julianToGregorian(parseInt(JULIAN_DATE)));
        break;
        case 'R':
            //ordinal date format YYYYDDD
            return formatDate(ordinalDate(parseInt(JULIAN_DATE)));
        break;
        default: return null;
    }
    
$$
;

 CREATE OR REPLACE FUNCTION REGEXP_LIKE_UDF(COL STRING, PATTERN STRING) 
RETURNS BOOLEAN
LANGUAGE JAVASCRIPT
IMMUTABLE
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"udf"}}'
AS
$$
return COL.match(new RegExp(PATTERN));
$$;

 CREATE OR REPLACE FUNCTION REGEXP_LIKE_UDF(COL STRING, PATTERN STRING, MATCHPARAM STRING) 
RETURNS BOOLEAN
LANGUAGE JAVASCRIPT
IMMUTABLE
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"udf"}}'
AS
$$
return COL.match(new RegExp(PATTERN, MATCHPARAM));
$$;

 --Create Table
CREATE TABLE timestampdiff_table (col1 TIMESTAMP, col2 TIMESTAMP);

--Insert data
INSERT INTO timestampdiff_table VALUES ('2000-03-20 22:01:11', '1996-03-20 10:01:11');
INSERT INTO timestampdiff_table VALUES ('1996-03-20 22:01:11', '2000-03-20 10:01:11');
INSERT INTO timestampdiff_table VALUES ('1982-05-11 22:31:19', '1900-01-25 15:21:15');
INSERT INTO timestampdiff_table VALUES ('1999-12-25 01:15:16', '1900-12-11 02:05:16');

--Select
SELECT col1 - col2 FROM timestampdiff_table;

COL1-COL2      |
---------------+
1461 12:0:0.0  |
-1460 12:0:0.0 |
30056 7:10:4.0 |
36172 23:10:0.0|

 --Create Table
CREATE OR REPLACE TABLE timestampdiff_table (col1 TIMESTAMP(6),
col2 TIMESTAMP(6)
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;

--Insert data
INSERT INTO timestampdiff_table
VALUES ('2000-03-20 22:01:11', '1996-03-20 10:01:11');

INSERT INTO timestampdiff_table
VALUES ('1996-03-20 22:01:11', '2000-03-20 10:01:11');

INSERT INTO timestampdiff_table
VALUES ('1982-05-11 22:31:19', '1900-01-25 15:21:15');

INSERT INTO timestampdiff_table
VALUES ('1999-12-25 01:15:16', '1900-12-11 02:05:16');

--Select
SELECT
PUBLIC.TIMESTAMP_DIFF_UDF( col1, col2) FROM
timestampdiff_table;

TIMESTAMP_DIFF_UDF( COL1, COL2)|
-------------------------------+
+000001461  12:00:00.00000000  |
-000001460  12:00:00.00000000  |
+000030056  07:10:04.00000000  |
+000036172  23:10:00.00000000  |

 SELECT
TRUNC(
	TO_TIMESTAMP ( '20-Mar-1996 21:01:11 ', 'DD-Mon-YYYY HH24:MI:SS' )
	)
"Date" FROM DUAL;

 SELECT
TRUNC(
	TO_TIMESTAMP ( '20-Mar-1996 21:01:11 ', 'DD-Mon-YYYY HH24:MI:SS' ), 'DD'
	)
"Date" FROM DUAL;

 SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YYYY') FROM DUAL UNION ALL 
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YEAR') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YYY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'Y') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'Q') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MONTH') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MON') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MM') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'DD') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'HH') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MI') FROM DUAL;

 SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YYYY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YEAR') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YYY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'YY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'Y') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'Q') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MONTH') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MON') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MM') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'DD') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'HH') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'MI') FROM DUAL;

 SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS')) FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'SYYYY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'SYEAR') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'RM') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'IW') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'DDD') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'J') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'HH12') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'HH24') FROM DUAL;

 SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'DD') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'YYYY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'YEAR') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'MM') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'WK') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'DD') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'D') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'HH') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'), 'HH') FROM DUAL;

 SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'DAY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'DY') FROM DUAL UNION ALL
SELECT TRUNC(TO_DATE('20/04/2022 13:21:10','DD/MM/YYYY HH24:MI:SS'),'D') FROM DUAL;