Oracle 18c

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CREATE OR REPLACE FUNCTION RESET_SEQUENCE(pinSequence    IN VARCHAR2,
                                          pinStart_value IN NUMBER DEFAULT 1,
                                          pinIncrement   IN NUMBER DEFAULT 1)
  RETURN NUMBER
AS
  nVal  NUMBER;
BEGIN
  -- Get the next value from the sequence

  EXECUTE IMMEDIATE 'SELECT ' || pinSequence || '.NEXTVAL ' ||
                    '  FROM DUAL'
    INTO nVal;
  
  -- Change the sequence so it decrements or increments to the desired
  -- start value the next time NEXTVAL is invoked.
  
  EXECUTE IMMEDIATE 'ALTER SEQUENCE ' || pinSequence ||
                    '  INCREMENT BY ' || (nVal - (pinStart_value - pinIncrement)) * -1 ||
                    '  MINVALUE 0';

  -- Decrement/increment the sequence to the desired start value

  EXECUTE IMMEDIATE 'SELECT ' || pinSequence || '.NEXTVAL ' ||
                    '  FROM DUAL'
    INTO nVal;
  
  -- Reset the sequence so it uses the desired "increment-by"
  
  EXECUTE IMMEDIATE 'ALTER SEQUENCE ' || pinSequence ||
                    '  INCREMENT BY ' || pinIncrement ||
                    '  MINVALUE 0';
  
  RETURN 1;
EXCEPTION
  WHEN OTHERS THEN
    DBMS_OUTPUT.PUT_LINE('RESET_SEQUENCE : ' || SQLCODE || ' ' || SQLERRM);
CREATE SEQUENCE MY_SEQUENCE
  INCREMENT BY 1
  NOMAXVALUE
  MINVALUE 1
  NOCYCLE
  NOCACHE;
DECLARE
  strSequence_name  VARCHAR2(32767);
  nVal              NUMBER;
  nReset            NUMBER;
BEGIN
  strSequence_name := 'MY_SEQUENCE';

  EXECUTE IMMEDIATE 'SELECT ' || strSequence_name || '.NEXTVAL FROM DUAL'
    INTO nVal;
  DBMS_OUTPUT.PUT_LINE('nVal = ' || nVal);

  EXECUTE IMMEDIATE 'SELECT ' || strSequence_name || '.NEXTVAL FROM DUAL'
    INTO nVal;
  DBMS_OUTPUT.PUT_LINE('nVal = ' || nVal);

  EXECUTE IMMEDIATE 'SELECT ' || strSequence_name || '.NEXTVAL FROM DUAL'
    INTO nVal;
  DBMS_OUTPUT.PUT_LINE('nVal = ' || nVal);

  EXECUTE IMMEDIATE 'SELECT ' || strSequence_name || '.NEXTVAL FROM DUAL'
    INTO nVal;
  DBMS_OUTPUT.PUT_LINE('nVal = ' || nVal);

  nReset := RESET_SEQUENCE(strSequence_name, 10, 2);
  DBMS_OUTPUT.PUT_LINE('nReset = ' || nReset);

  EXECUTE IMMEDIATE 'SELECT ' || strSequence_name || '.NEXTVAL FROM DUAL'
    INTO nVal;
  DBMS_OUTPUT.PUT_LINE('nVal = ' || nVal);

  EXECUTE IMMEDIATE 'SELECT ' || strSequence_name || '.NEXTVAL FROM DUAL'
    INTO nVal;
  DBMS_OUTPUT.PUT_LINE('nVal = ' || nVal);

  EXECUTE IMMEDIATE 'SELECT ' || strSequence_name || '.NEXTVAL FROM DUAL'
    INTO nVal;
1 rows affected

dbms_output:
nVal = 1
nVal = 2
nVal = 3
nVal = 4
nReset = 1
nVal = 10
nVal = 12
nVal = 14
nVal = 16
nReset = 1
nVal = 1
nVal = 2
nVal = 3
nVal = 4
nReset = 1
nVal = 1000
nVal = 1010
nVal = 1020
nVal = 1030