FORALL

Description

The FORALL statement runs one DML statement multiple times, with different values in the VALUES and WHERE clauses. (Oracle PL/SQL Language Reference FORALL Statement).

FORALL index IN bounds_clause [ SAVE ] [ EXCEPTIONS ] dml_statement ;

Sample Source Patterns

Setup Data

Oracle

IN -> Oracle_01.sql
CREATE TABLE table1 (
    column1 NUMBER,
    column2 NUMBER
);

INSERT INTO table1 (column1, column2) VALUES (1, 2);
INSERT INTO table1 (column1, column2) VALUES (2, 3);
INSERT INTO table1 (column1, column2) VALUES (3, 4);
INSERT INTO table1 (column1, column2) VALUES (4, 5);
INSERT INTO table1 (column1, column2) VALUES (5, 6);

CREATE TABLE table2 (
    column1 NUMBER,
    column2 NUMBER
);

INSERT INTO table2 (column1, column2) VALUES (1, 2);

Snowflake

OUT -> Oracle_01.sql
CREATE OR REPLACE TABLE table1 (
    column1 NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/,
    column2 NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;

INSERT INTO table1(column1, column2) VALUES (1, 2);

INSERT INTO table1(column1, column2) VALUES (2, 3);

INSERT INTO table1(column1, column2) VALUES (3, 4);

INSERT INTO table1(column1, column2) VALUES (4, 5);

INSERT INTO table1(column1, column2) VALUES (5, 6);

CREATE OR REPLACE TABLE table2 (
    column1 NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/,
    column2 NUMBER(38, 18) /*** SSC-FDM-0006 - NUMBER TYPE COLUMN MAY NOT BEHAVE SIMILARLY IN SNOWFLAKE. ***/
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;

INSERT INTO table2(column1, column2) VALUES (1, 2);

1. FORALL With Collection of Records

Oracle

IN -> Oracle_03.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS SELECT * FROM table1;
    TYPE tableType IS TABLE OF cursorVariable%ROWTYPE;
    tableVariable tableType;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO tableVariable LIMIT 100;
        EXIT WHEN tableVariable.COUNT = 0;

        FORALL forIndex IN 1..tableVariable.COUNT
            INSERT INTO table2 (column1, column2)
            VALUES (tableVariable(forIndex).column1, tableVariable(forIndex).column2);
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_03.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2(column1, column2)
        (
            SELECT
                column1,
                column2
            FROM
                table1
        );
    END;
$$;

The EWIs SSC-PRF-0001 and SSC-PRF-0003 are added in every FETCH BULK COLLECT occurrence into FORALL statement.

2. FORALL With INSERT INTO

Oracle

IN -> Oracle_04.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;
    TYPE collectionTypeDefinition IS TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 2;
        EXIT WHEN collectionVariable.COUNT = 0;
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            INSERT INTO table2 VALUES collectionVariable(forIndex);
        collectionVariable.DELETE;
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_04.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                * FROM
                table1
        );
    END;
$$;

3. FORALL With Multiple Fetched Collections

Oracle

IN -> Oracle_05.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;
    column1Collection dbms_sql.NUMBER_table;
    column2Collection dbms_sql.NUMBER_table;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO column1Collection, column2Collection limit 20;
        EXIT WHEN column1Collection.COUNT = 0;
        FORALL forIndex IN 1..column1Collection.COUNT
            INSERT INTO table2 VALUES (
                column1Collection(forIndex),
                column2Collection(forIndex)
            );
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_05.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                $1,
                $2
            FROM
                table1
        );
    END;
$$;

4. FORALL With Record of Collections

Oracle

IN -> Oracle_07.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;
    TYPE recordType IS RECORD(
        column1Collection dbms_sql.NUMBER_table,
        column2Collection dbms_sql.NUMBER_table
    );
    columnRecord recordType;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO columnRecord.column1Collection, columnRecord.column2Collection limit 20;
        FORALL forIndex IN 1..columnRecord.column1Collection.COUNT
            INSERT INTO table2 VALUES (
                columnRecord.column1Collection(forIndex),
                columnRecord.column2Collection(forIndex)
            );
        EXIT WHEN cursorVariable%NOTFOUND;
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_07.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                $1,
                $2
            FROM
                table1
        );
    END;
$$;

5. FORALL With Dynamic SQL

Oracle

IN -> Oracle_08.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    cursorVariable SYS_REFCURSOR;
    TYPE collectionTypeDefinition IS
        TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
    query VARCHAR(200) := 'SELECT * FROM table1';
BEGIN
    OPEN cursorVariable FOR query;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable;
        EXIT WHEN collectionVariable.COUNT = 0;
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            INSERT INTO table2 VALUES collectionVariable(forIndex);
        collectionVariable.DELETE;
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_08.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$
    DECLARE
        query VARCHAR(200) := 'SELECT * FROM
   table1';
    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        !!!RESOLVE EWI!!! /*** SSC-EWI-0030 - THE STATEMENT BELOW HAS USAGES OF DYNAMIC SQL. ***/!!!
        EXECUTE IMMEDIATE 'CREATE OR REPLACE TEMPORARY TABLE query AS ' || :query;
        INSERT INTO table2
        (
            SELECT
                *
            FROM
                query
        );
    END;
$$;

6. FORALL With Literal SQL

Oracle

IN -> Oracle_09.sql
CREATE OR REPLACE PROCEDURE SampleProcedure
IS
TYPE TabRecType IS RECORD (
    column1 NUMBER,
    column2 NUMBER
);
TYPE tabType IS TABLE OF TabRecType;
cursorRef SYS_REFCURSOR;
tab tabType;
BEGIN
    OPEN cursorRef FOR 'SELECT src.column1, src.column2 FROM ' || 'table1' || ' src';

    LOOP
        BEGIN
            FETCH cursorRef BULK COLLECT INTO tab LIMIT 1000;
            FORALL i IN 1..tab.COUNT
                INSERT INTO table2 (column1, column2)
                VALUES (tab(i).column1, tab(i).column2);

            EXIT WHEN cursorRef%NOTFOUND;
        END;
    END LOOP;

    CLOSE cursorRef;
END;

Snowflake

OUT -> Oracle_09.sql
CREATE OR REPLACE PROCEDURE SampleProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        EXECUTE IMMEDIATE 'CREATE OR REPLACE TEMPORARY TABLE cursorRef_TEMP_TABLE AS ' || 'SELECT src.column1, src.column2 FROM ' || 'table1' || ' src';
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2(column1, column2)
        (
            SELECT
                *
            FROM
                cursorRef_TEMP_TABLE
        );
    END;
$$;

7. FORALL With Parametrized Cursors

Oracle

IN -> Oracle_10.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    intVariable INTEGER := 7;
    CURSOR cursorVariable(param1 INTEGER, param2 INTEGER default 5) IS
        SELECT * FROM table1
        WHERE
            column2 = intVariable OR
            column1 BETWEEN param1 AND param2;
    TYPE collectionTypeDefinition IS
        TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
BEGIN
    OPEN cursorVariable(1);
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 20;
        EXIT WHEN collectionVariable.COUNT = 0;
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            INSERT INTO table2 VALUES collectionVariable(forIndex);
        collectionVariable.DELETE;
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_10.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$
    DECLARE
        intVariable INTEGER := 7;
    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                * FROM
                table1
                   WHERE
                       column2 = :intVariable
                OR
                       column1 BETWEEN 1 AND 5
        );
    END;
$$;

8. FORALL Without LOOPS

Oracle

IN -> Oracle_11.sql
CREATE OR REPLACE PROCEDURE  myProcedure IS
    TYPE collectionTypeDefinition IS TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
BEGIN
    SELECT * BULK COLLECT INTO collectionVariable FROM table1;
        FORALL forIndex IN 1..collectionVariable.COUNT
            INSERT INTO table2 VALUES (
                collectionVariable (forIndex).column1,
                collectionVariable (forIndex).column2
            );
        collectionVariable.DELETE;
END;

Snowflake

OUT -> Oracle_11.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                column1,
                column2
            FROM
                table1
        );
    END;
$$;

9. FORALL With UPDATE Statements

Oracle

IN -> Oracle_12.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;
    TYPE collectionTypeDefinition IS TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 2;
        EXIT WHEN collectionVariable.COUNT = 0;
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            UPDATE table2 SET column1 = '54321' WHERE column2 = collectionVariable(forIndex).column2;
        collectionVariable.DELETE;
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_12.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        UPDATE table2
            SET column1 = '54321'
            FROM
                (
                    SELECT
                        * FROM
                        table1) AS collectionVariable
            WHERE
                column2 = collectionVariable.column2;
    END;
$$;

10. FORALL With DELETE Statements

Oracle

IN -> Oracle_13.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;
    TYPE collectionTypeDefinition IS TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 2;
        EXIT WHEN collectionVariable.COUNT = 0;
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            DELETE FROM table2 WHERE column2 = collectionVariable(forIndex).column2;
        collectionVariable.DELETE;
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_13.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        DELETE FROM
            table2
        USING (
            SELECT
                * FROM
                table1) collectionVariable
                WHERE
            table2.column2 = collectionVariable.column2;
    END;
$$;

11. FORALL With PACKAGE References

Oracle

IN -> Oracle_14.sql
CREATE OR REPLACE PACKAGE MyPackage AS
    TYPE collectionTypeDefinition IS
        TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
END;
/
 
CREATE OR REPLACE PROCEDURE InsertIntoPackage(param integer) IS
BEGIN
    SELECT
        param,
        param BULK COLLECT INTO MyPackage.collectionVariable
    FROM
        DUAL;
END;
/
 
CREATE OR REPLACE PROCEDURE InsertUsingPackage IS
BEGIN
        FORALL forIndex IN MyPackage.collectionVariable.FIRST..MyPackage.collectionVariable.LAST
            INSERT INTO table2 VALUES MyPackage.collectionVariable(forIndex);
        MyPackage.collectionVariable.DELETE;
END;
/

DECLARE
    param_value INTEGER := 10;
BEGIN
    InsertIntoPackage(param_value);
    InsertUsingPackage;
END;

select * from table2;

Snowflake

OUT -> Oracle_14.sql
CREATE SCHEMA IF NOT EXISTS MyPackage
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;

!!!RESOLVE EWI!!! /*** SSC-EWI-OR0049 - PACKAGE TYPE DEFINITIONS in stateful package MyPackage are not supported yet ***/!!!
TYPE collectionTypeDefinition IS
    TABLE OF table1%ROWTYPE;

CREATE OR REPLACE TEMPORARY TABLE MYPACKAGE_COLLECTIONVARIABLE (
);

CREATE OR REPLACE PROCEDURE InsertIntoPackage (param integer)
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$
    BEGIN
        DELETE FROM
            MYPACKAGE_COLLECTIONVARIABLE;
        INSERT INTO MYPACKAGE_COLLECTIONVARIABLE
        (
            SELECT
                :param,
                :param
            FROM
        DUAL
        );
    END;
$$;

CREATE OR REPLACE PROCEDURE InsertUsingPackage ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                *
            FROM
                MYPACKAGE_COLLECTIONVARIABLE
        );
    END;
$$;

DECLARE
    param_value INTEGER := 10;
    call_results VARIANT;
BEGIN
    CALL
    InsertIntoPackage(:param_value);
    CALL
    InsertUsingPackage();
    RETURN call_results;
END;

select * from
    table2;

12. FORALL With MERGE Statements

Oracle

IN -> Oracle_15.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;
    TYPE collectionTypeDefinition IS
        TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 2;
        EXIT WHEN collectionVariable.COUNT = 0;
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
        MERGE INTO table2 tgt
            USING (
                SELECT
                    collectionVariable(forIndex).column1 column1,
                    collectionVariable(forIndex).column2 column2
                FROM DUAL
            ) src
           ON (tgt.column1 = src.column1)
        WHEN MATCHED THEN
            UPDATE SET
               tgt.column2 = src.column2 * 2
        WHEN NOT MATCHED THEN
            INSERT (column1, column2)
            VALUES (src.column1, src.column2);
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_15.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        MERGE INTO table2 tgt
            USING (
                SELECT
                    collectionVariable.column1 column1,
                    collectionVariable.column2 column2
                FROM
                    (
                        SELECT
                            * FROM
                            table1
                    ) collectionVariable
            ) src
           ON (tgt.column1 = src.column1)
        WHEN MATCHED THEN
            UPDATE SET
               tgt.column2 = src.column2 * 2
        WHEN NOT MATCHED THEN
            INSERT (column1, column2)
            VALUES (src.column1, src.column2);
    END;
$$;

13. Default FORALL transformation

You might also be interested in Bulk Cursor Helpers.

Oracle

IN -> Oracle_16.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS SELECT * FROM table1;
    TYPE columnsRecordType IS RECORD (column1 dbms_sql.NUMBER_table, column2 dbms_sql.NUMBER_table);
    recordVariable columnsRecordType;
    TYPE collectionTypeDefinition IS TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
    col1 dbms_sql.NUMBER_table;
    col2 dbms_sql.NUMBER_table;
BEGIN
    OPEN cursorVariable;
    FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 2;
    FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
        INSERT INTO table2 (column1, column2)
        VALUES (collectionVariable(forIndex).column1, collectionVariable(forIndex).column2);

    FETCH cursorVariable BULK COLLECT INTO col1, col2 limit 2;
    FORALL forIndex IN col1.FIRST..col1.LAST
        INSERT INTO table2 (column1, column2)
        VALUES (col1(forIndex), col2(forIndex));

    LOOP
        FETCH cursorVariable BULK COLLECT INTO recordVariable limit 2;
        EXIT WHEN recordVariable.column1.COUNT = 0;
        FORALL forIndex IN recordVariable.column1.FIRST..recordVariable.column1.LAST
            INSERT INTO table2 (column1, column2)
            VALUES (recordVariable.column1(forIndex), recordVariable.column2(forIndex));
    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_16.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$
    DECLARE
        cursorVariable OBJECT := INIT_CURSOR_UDF('cursorVariable', '   SELECT * FROM
      table1');
        !!!RESOLVE EWI!!! /*** SSC-EWI-0056 - CUSTOM TYPES ARE NOT SUPPORTED IN SNOWFLAKE BUT REFERENCES TO THIS CUSTOM TYPE WERE CHANGED TO OBJECT ***/!!!
           TYPE columnsRecordType IS RECORD (column1 dbms_sql.NUMBER_table, column2 dbms_sql.NUMBER_table);
           recordVariable OBJECT !!!RESOLVE EWI!!! /*** SSC-EWI-0036 - columnsRecordType DATA TYPE CONVERTED TO OBJECT ***/!!! := OBJECT_CONSTRUCT();
--        !!!RESOLVE EWI!!! /*** SSC-EWI-0058 - FUNCTIONALITY FOR 'PL COLLECTION TYPE DEFINITION' IS NOT CURRENTLY SUPPORTED BY SNOWFLAKE SCRIPTING ***/!!!
--           TYPE collectionTypeDefinition IS TABLE OF table1%ROWTYPE;
           collectionVariable VARIANT !!!RESOLVE EWI!!! /*** SSC-EWI-0062 - CUSTOM TYPE 'collectionTypeDefinition' USAGE CHANGED TO VARIANT ***/!!!;
           col1 VARIANT /*** SSC-FDM-0015 - REFERENCED CUSTOM TYPE 'dbms_sql.NUMBER_table' IN QUERY NOT FOUND, USAGES MAY BE AFFECTED ***/;
           col2 VARIANT /*** SSC-FDM-0015 - REFERENCED CUSTOM TYPE 'dbms_sql.NUMBER_table' IN QUERY NOT FOUND, USAGES MAY BE AFFECTED ***/;
        FORALL INTEGER;
    BEGIN
        cursorVariable := (
            CALL OPEN_BULK_CURSOR_UDF(:cursorVariable)
        );
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        cursorVariable := (
            CALL FETCH_BULK_COLLECTION_RECORDS_UDF(:cursorVariable, 2)
        );
        collectionVariable := :cursorVariable:RESULT;
        FORALL := ARRAY_SIZE(:collectionVariable);
        INSERT INTO table2(column1, column2)
        (
            SELECT
                :collectionVariable[forIndex]:column1,
                : collectionVariable[forIndex]:column2
            FROM
                (
                    SELECT
                        seq4() AS forIndex
                    FROM
                        TABLE(GENERATOR(ROWCOUNT => :FORALL))
                )
        );
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        cursorVariable := (
            CALL FETCH_BULK_COLLECTIONS_UDF(:cursorVariable, 2)
        );
        col1 := :cursorVariable:RESULT[0];
        col2 := :cursorVariable:RESULT[1];
        FORALL := ARRAY_SIZE(:col1);
        INSERT INTO table2(column1, column2)
        (
            SELECT
                :col1[forIndex],
                : col2[forIndex]
            FROM
                (
                    SELECT
                        seq4() AS forIndex
                    FROM
                        TABLE(GENERATOR(ROWCOUNT => :FORALL))
                )
        );
        LOOP
            --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
            --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
            cursorVariable := (
                CALL FETCH_BULK_RECORD_COLLECTIONS_UDF(:cursorVariable, 2)
            );
            recordVariable := :cursorVariable:RESULT;
            IF (ARRAY_SIZE(:recordVariable:column1) = 0) THEN
                EXIT;
            END IF;
            FORALL := ARRAY_SIZE(:recordVariable:column1);
            INSERT INTO table2(column1, column2)
            (
                SELECT
                    :recordVariable:column1[forIndex],
                    : recordVariable:column2[forIndex]
                FROM
                    (
                        SELECT
                            seq4() AS forIndex
                        FROM
                            TABLE(GENERATOR(ROWCOUNT => :FORALL))
                    )
            );
        END LOOP;
        cursorVariable := (
            CALL CLOSE_BULK_CURSOR_UDF(:cursorVariable)
        );
    END;
$$;

This transformation is done only when none of the previously mentioned transformations can be done.

14. Multiple FORALL inside a LOOP clause

This pattern applies when there is more than one FORALL in the same procedure and it meets the following structure.

Oracle

IN -> Oracle_17.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;

    TYPE collectionTypeDefinition IS TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 20;
        EXIT WHEN collectionVariable.COUNT = 0;

        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            INSERT INTO table2 VALUES collectionVariable(forIndex);
        
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            UPDATE table2 SET column1 = '54321' WHERE column2 = collectionVariable(forIndex).column2;

    END LOOP;
    CLOSE cursorVariable;
END;

Snowflake

OUT -> Oracle_17.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                * FROM
                table1
        );
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        UPDATE table2
            SET column1 = '54321'
            FROM
                (
                    SELECT
                        * FROM
                        table1) AS collectionVariable
            WHERE
                column2 = collectionVariable.column2;
    END;
$$;

15. Multiple FORALL inside different LOOP clauses

This pattern applies when there is more than one FORALL in the same procedure and it meets the following structure.

Oracle

IN -> Oracle_18.sql
CREATE OR REPLACE PROCEDURE myProcedure IS
    CURSOR cursorVariable IS
        SELECT * FROM table1;

    CURSOR cursorVariable2 IS
        SELECT * FROM table1;

    TYPE collectionTypeDefinition IS
        TABLE OF table1%ROWTYPE;
    collectionVariable collectionTypeDefinition;

    TYPE collectionTypeDefinition2 IS
        TABLE OF table1%ROWTYPE;
    collectionVariable2 collectionTypeDefinition2;
BEGIN
    OPEN cursorVariable;
    LOOP
        FETCH cursorVariable BULK COLLECT INTO collectionVariable limit 2;
        EXIT WHEN collectionVariable.COUNT = 0;
        FORALL forIndex IN collectionVariable.FIRST..collectionVariable.LAST
            INSERT INTO table2 VALUES collectionVariable(forIndex);
    END LOOP;
    CLOSE cursorVariable;

    OPEN cursorVariable2;
    LOOP
        FETCH cursorVariable2 BULK COLLECT INTO collectionVariable2 limit 2;
        EXIT WHEN collectionVariable2.COUNT = 0;
        FORALL forIndex IN collectionVariable2.FIRST..collectionVariable2.LAST
            UPDATE table2 SET column1 = '54321' WHERE column2 = collectionVariable2(forIndex).column2;
    END LOOP;
    CLOSE cursorVariable2;
END;

Snowflake

OUT -> Oracle_18.sql
CREATE OR REPLACE PROCEDURE myProcedure ()
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$

    BEGIN
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        INSERT INTO table2
        (
            SELECT
                * FROM
                table1
        );
        --** SSC-PRF-0001 - THIS STATEMENT HAS USAGES OF CURSOR FETCH BULK OPERATIONS **
        --** SSC-PRF-0003 - FETCH INSIDE A LOOP IS CONSIDERED A COMPLEX PATTERN, THIS COULD DEGRADE SNOWFLAKE PERFORMANCE. **
        UPDATE table2
            SET column1 = '54321'
            FROM
                (
                    SELECT
                        * FROM
                        table1) AS collectionVariable2
            WHERE
                column2 = collectionVariable2.column2;
    END;
$$;

16. FORALL with MERGE INTO with LOG ERRORS

Oracle

CREATE OR REPLACE PROCEDURE procedure_example (
    department_id_in   IN source_table.DepartmentID%TYPE)
IS
    TYPE employee_ids_t IS TABLE OF source_table%ROWTYPE
    INDEX BY PLS_INTEGER; 
    employee_list   employee_ids_t;
BEGIN
    SELECT *
        BULK COLLECT INTO employee_list
        FROM source_table
        WHERE DepartmentID = procedure_example.department_id_in;
    
    FORALL indx IN 1 .. employee_list.COUNT
      MERGE INTO target_table 
      USING (SELECT * FROM DUAL) src
      ON (id = employee_list(indx).id)
      WHEN MATCHED THEN
        UPDATE SET
          name = employee_list(indx).Name
      WHEN NOT MATCHED THEN
        INSERT (Id, Name, DepartmentID)
        VALUES (employee_list(indx).Id, employee_list(indx).Name, employee_list(indx).DepartmentID)
      LOG ERRORS INTO error_table('MERGE INTO ERROR') 
      REJECT LIMIT UNLIMITED;
        
END;

CALL procedure_example(10);

select * from target_table;
select * from error_table;

Snowflake

--Generated by SnowConvert---------------
CREATE OR REPLACE TRANSIENT TABLE target_staging_table(
  Id INT PRIMARY KEY,
  Name VARCHAR2(10) NOT NULL,
  DepartmentID INT REFERENCES parent_table(Id)
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;
--Generated by SnowConvert---------------

CREATE OR REPLACE PROCEDURE procedure_example (DEPARTMENT_ID_IN INT /*** MSC-WARNING - MSCEWI3129 - TYPE ATTRIBUTE 'employees.DepartmentID%TYPE' COULD NOT BE RESOLVED, SO IT WAS TRANSFORMED TO VARIANT ***/)
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$  
    BEGIN
        CREATE OR REPLACE TEMP TABLE SOURCE_TEMPORAL AS
        WITH source_data as (
            SELECT *
            FROM source_table
            WHERE DEPARTMENTID =: DEPARTMENT_ID_IN
        )
        SELECT source_data.*, parent_table.id as PARENT_KEY 
        FROM source_data 
        left join parent_table on source_data.DepartmentID = parent_table.id;
        
        --All records violating foreign key integrity
        INSERT INTO error_table (ERROR, COLUMN_NAME, REJECTED_RECORD)
        SELECT 
            'Foreign Key Constraint Violated' ERROR,'KEY_COL' COLUMN_NAME, id
        FROM SOURCE_TEMPORAL 
        WHERE PARENT_KEY IS NULL;


        DELETE FROM SOURCE_TEMPORAL 
        WHERE PARENT_KEY IS NULL;

        BEGIN
            MERGE INTO target_table
            USING SOURCE_TEMPORAL SRC
            ON SRC.id = target_table.id
            WHEN MATCHED THEN
                UPDATE SET 
                    name = SRC.name
            WHEN NOT MATCHED THEN
               INSERT (Id, Name, DepartmentID)
               VALUES (SRC.Id, SRC.Name, SRC.DepartmentID);
        EXCEPTION
            WHEN OTHER THEN
                CREATE OR REPLACE TEMPORARY STAGE my_int_stage
                  COPY_OPTIONS = (ON_ERROR='continue');
                
                --Create my file and populate with data
                COPY INTO @my_int_stage/my_file FROM (
                SELECT  * exclude(PARENT_KEY) FROM SOURCE_TEMPORAL
                ) OVERWRITE = TRUE ;

                COPY INTO target_staging_table(id, name, DepartmentID) 
                FROM (
                  SELECT 
                    -- distinct
                    t.$1, t.$2, t.$3 
                  FROM @my_int_stage/my_file t
                  ) ON_ERROR = CONTINUE;

                INSERT INTO ERROR_TABLE (ERROR, FILE, LINE, CHARACTER, CATEGORY, CODE, SQL_STATE, COLUMN_NAME, ROW_NUMBER, REJECTED_RECORD)
                SELECT 
                    ERROR, FILE,LINE, CHARACTER, CATEGORY, CODE, SQL_STATE, COLUMN_NAME, ROW_NUMBER, REJECTED_RECORD
                FROM TABLE(VALIDATE(target_staging_table, JOB_ID => '_last')) order by line; --The last charge on the current session

                MERGE INTO target_table
                USING target_staging_table staging
                ON staging.id = target_table.id
                WHEN MATCHED THEN
                    UPDATE SET 
                        name = staging.name
                WHEN NOT MATCHED THEN
                INSERT (Id, Name, DepartmentID)
                VALUES (staging.Id, staging.Name, staging.DepartmentID);
        END;

        return 'Awesome!';
    END;
$$;

CALL procedure_example(10);

SELECT * FROM target_table;
SELECT * FROM error_table;

17. FORALL with INSERT with LOG ERRORS

Oracle

CREATE OR REPLACE PROCEDURE procedure_example (
    department_id_in   IN source_table.DepartmentID%TYPE)
IS
    TYPE employee_ids_t IS TABLE OF source_table%ROWTYPE
    INDEX BY PLS_INTEGER; 
    employee_list   employee_ids_t;
BEGIN
    SELECT *
        BULK COLLECT INTO employee_list
        FROM source_table
        WHERE DepartmentID = procedure_example.department_id_in;
    
    FORALL indx IN 1 .. employee_list.COUNT
        INSERT INTO target_table(Id, Name, DepartmentID)
        VALUES (employee_list(indx).Id, employee_list(indx).Name, employee_list(indx).DepartmentID)
        LOG ERRORS INTO error_table('MERGE INTO ERROR') 
        REJECT LIMIT UNLIMITED;
END;

Snowflake

--Generated by SnowConvert---------------
CREATE OR REPLACE TRANSIENT TABLE target_staging_table(
  Id INT PRIMARY KEY,
  Name VARCHAR2(10) NOT NULL,
  DepartmentID INT REFERENCES parent_table(Id)
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
;
--Generated by SnowConvert---------------

CREATE OR REPLACE PROCEDURE procedure_example (DEPARTMENT_ID_IN INT /*** MSC-WARNING - MSCEWI3129 - TYPE ATTRIBUTE 'employees.DepartmentID%TYPE' COULD NOT BE RESOLVED, SO IT WAS TRANSFORMED TO VARIANT ***/)
RETURNS VARCHAR
LANGUAGE SQL
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"oracle"}}'
EXECUTE AS CALLER
AS
$$  
    BEGIN
        CREATE OR REPLACE TEMP TABLE SOURCE_TEMPORAL AS
        WITH source_data as (
            SELECT *
            FROM source_table
            WHERE DEPARTMENTID =: DEPARTMENT_ID_IN
        )
        SELECT source_data.*, parent_table.id as PARENT_KEY 
        FROM source_data 
        left join parent_table on source_data.DepartmentID = parent_table.id;
        
        --All records violating foreign key integrity
        INSERT INTO error_table (ERROR, COLUMN_NAME, REJECTED_RECORD)
        SELECT 
            'Foreign Key Constraint Violated' ERROR,'KEY_COL' COLUMN_NAME, id
        FROM SOURCE_TEMPORAL 
        WHERE PARENT_KEY IS NULL;


        DELETE FROM SOURCE_TEMPORAL 
        WHERE PARENT_KEY IS NULL;

        BEGIN
            INSERT INTO target_table (Id, Name, DepartmentID)
            SELECT SRC.Id, SRC.Name, SRC.DepartmentID FROM SOURCE_TEMPORAL SRC;
        EXCEPTION
            WHEN OTHER THEN
                CREATE OR REPLACE TEMPORARY STAGE my_int_stage
                  COPY_OPTIONS = (ON_ERROR='continue');
                
                --Create my file and populate with data
                COPY INTO @my_int_stage/my_file FROM (
                SELECT  * exclude(PARENT_KEY) FROM SOURCE_TEMPORAL
                ) OVERWRITE = TRUE ;

                COPY INTO target_staging_table(id, name, DepartmentID) 
                FROM (
                  SELECT 
                    -- distinct
                    t.$1, t.$2, t.$3 
                  FROM @my_int_stage/my_file t
                  ) ON_ERROR = CONTINUE;

                INSERT INTO ERROR_TABLE (ERROR, FILE, LINE, CHARACTER, CATEGORY, CODE, SQL_STATE, COLUMN_NAME, ROW_NUMBER, REJECTED_RECORD)
                SELECT 
                    ERROR, FILE,LINE, CHARACTER, CATEGORY, CODE, SQL_STATE, COLUMN_NAME, ROW_NUMBER, REJECTED_RECORD
                FROM TABLE(VALIDATE(target_staging_table, JOB_ID => '_last')) order by line; --The last charge on the current session

                INSERT INTO target_table (Id, Name, DepartmentID)
                SELECT staging.Id, staging.Name, staging.DepartmentID FROM target_staging_table staging;
        END;
    END;
$$;

CALL procedure_example(10);

SELECT * FROM target_table;
SELECT * FROM error_table;

Known Issues

No issues were found.

  1. SSC-EWI-0030: The statement below has usages of dynamic SQL.

  2. SSC-EWI-0036: Data type converted to another data type.

  3. SSC-EWI-0056: Create Type Not Supported.

  4. SSC-EWI-0058: Functionality is not currently supported by Snowflake Scripting.

  5. SSC-EWI-0062: Custom type usage changed to variant.

  6. SSC-EWI-OR0049: Package constants in stateful package are not supported yet.

  7. SSC-FDM-0006: Number type column may not behave similarly in Snowflake.

  8. SSC-FDM-0015: ​Referenced custom type in query not found.

  9. SSC-PRF-0001: This statement has usages of cursor fetch bulk operations.

  10. SSC-PRF-0003: Fetch inside a loop is considered a complex pattern, this could degrade Snowflake performance.

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