Oracle 21c

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CREATE TABLE table_name (id PRIMARY KEY) AS
SELECT LEVEL FROM DUAL CONNECT BY LEVEL <= 1000;
1000 rows affected

BEGIN
  EXECUTE IMMEDIATE
    'EXPLAIN PLAN FOR SELECT * FROM table_name WHERE id IN (:a, :b, :c, :d)'
    USING 1, 2, 57, 932;
END;
/
1 rows affected

SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY());

PLAN_TABLE_OUTPUT

Plan hash value: 921109922

------------------------------------------------------------------------------------

| Id  | Operation          | Name          | Rows  | Bytes | Cost (%CPU)| Time     |

------------------------------------------------------------------------------------

|   0 | SELECT STATEMENT   |               |     4 |    16 |     2   (0)| 00:00:01 |

|   1 |  INLIST ITERATOR   |               |       |       |            |          |

|*  2 |   INDEX UNIQUE SCAN| SYS_C00100786 |     4 |    16 |     2   (0)| 00:00:01 |

------------------------------------------------------------------------------------

Predicate Information (identified by operation id):

---------------------------------------------------

   2 - access("ID"=TO_NUMBER(:A) OR "ID"=TO_NUMBER(:B) OR

              "ID"=TO_NUMBER(:C) OR "ID"=TO_NUMBER(:D))

BEGIN
  EXECUTE IMMEDIATE
    'EXPLAIN PLAN FOR SELECT * FROM table_name WHERE id IN (:a, :b, :c, :d)'
    USING 2, 2, 2, 2;
END;
/
1 rows affected

SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY());

PLAN_TABLE_OUTPUT

Plan hash value: 921109922

------------------------------------------------------------------------------------

| Id  | Operation          | Name          | Rows  | Bytes | Cost (%CPU)| Time     |

------------------------------------------------------------------------------------

|   0 | SELECT STATEMENT   |               |     4 |    16 |     2   (0)| 00:00:01 |

|   1 |  INLIST ITERATOR   |               |       |       |            |          |

|*  2 |   INDEX UNIQUE SCAN| SYS_C00100786 |     4 |    16 |     2   (0)| 00:00:01 |

------------------------------------------------------------------------------------

Predicate Information (identified by operation id):

---------------------------------------------------

   2 - access("ID"=TO_NUMBER(:A) OR "ID"=TO_NUMBER(:B) OR

              "ID"=TO_NUMBER(:C) OR "ID"=TO_NUMBER(:D))

BEGIN
  EXECUTE IMMEDIATE
    'EXPLAIN PLAN FOR
     SELECT *
     FROM   table_name
     WHERE  id IN (:a,:b,:c,:d,:e,:f,:g,:h,:i,:j,:k,:l,:m,:n,:o,:p,:q,:r,:s,:t)'
    USING          2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2;
END;
/
1 rows affected

SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY());

PLAN_TABLE_OUTPUT

Plan hash value: 921109922

------------------------------------------------------------------------------------

| Id  | Operation          | Name          | Rows  | Bytes | Cost (%CPU)| Time     |

------------------------------------------------------------------------------------

|   0 | SELECT STATEMENT   |               |    20 |    80 |     2   (0)| 00:00:01 |

|   1 |  INLIST ITERATOR   |               |       |       |            |          |

|*  2 |   INDEX UNIQUE SCAN| SYS_C00100786 |    20 |    80 |     2   (0)| 00:00:01 |

------------------------------------------------------------------------------------

Predicate Information (identified by operation id):

---------------------------------------------------

   2 - access("ID"=TO_NUMBER(:A) OR "ID"=TO_NUMBER(:B) OR

              "ID"=TO_NUMBER(:C) OR "ID"=TO_NUMBER(:D) OR "ID"=TO_NUMBER(:E) OR

              "ID"=TO_NUMBER(:F) OR "ID"=TO_NUMBER(:G) OR "ID"=TO_NUMBER(:H) OR

              "ID"=TO_NUMBER(:I) OR "ID"=TO_NUMBER(:J) OR "ID"=TO_NUMBER(:K) OR

              "ID"=TO_NUMBER(:L) OR "ID"=TO_NUMBER(:M) OR "ID"=TO_NUMBER(:N) OR

              "ID"=TO_NUMBER(:O) OR "ID"=TO_NUMBER(:P) OR "ID"=TO_NUMBER(:Q) OR

              "ID"=TO_NUMBER(:R) OR "ID"=TO_NUMBER(:S) OR "ID"=TO_NUMBER(:T))

BEGIN
  EXECUTE IMMEDIATE
    'EXPLAIN PLAN FOR
     SELECT *
     FROM   table_name
     WHERE  id IN (2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2)';
END;
/
1 rows affected

SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY());

PLAN_TABLE_OUTPUT

Plan hash value: 3057245301

-----------------------------------------------------------------------------------

| Id  | Operation         | Name          | Rows  | Bytes | Cost (%CPU)| Time     |

-----------------------------------------------------------------------------------

|   0 | SELECT STATEMENT  |               |     1 |     4 |     1   (0)| 00:00:01 |

|*  1 |  INDEX UNIQUE SCAN| SYS_C00100786 |     1 |     4 |     1   (0)| 00:00:01 |

-----------------------------------------------------------------------------------

Predicate Information (identified by operation id):

---------------------------------------------------

   1 - access("ID"=2)

BEGIN
  EXECUTE IMMEDIATE
    'EXPLAIN PLAN FOR
     SELECT *
     FROM   table_name
     WHERE  id IN (1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4)';
END;
/
1 rows affected

SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY());

PLAN_TABLE_OUTPUT

Plan hash value: 921109922

------------------------------------------------------------------------------------

| Id  | Operation          | Name          | Rows  | Bytes | Cost (%CPU)| Time     |

------------------------------------------------------------------------------------

|   0 | SELECT STATEMENT   |               |     4 |    16 |     2   (0)| 00:00:01 |

|   1 |  INLIST ITERATOR   |               |       |       |            |          |

|*  2 |   INDEX UNIQUE SCAN| SYS_C00100786 |     4 |    16 |     2   (0)| 00:00:01 |

------------------------------------------------------------------------------------

Predicate Information (identified by operation id):

---------------------------------------------------

   2 - access("ID"=1 OR "ID"=2 OR "ID"=3 OR "ID"=4)

BEGIN
  EXECUTE IMMEDIATE
    'EXPLAIN PLAN FOR SELECT * FROM table_name WHERE id IN (:a)'
    USING 2;
END;
/
1 rows affected

SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY());

PLAN_TABLE_OUTPUT

Plan hash value: 3057245301

-----------------------------------------------------------------------------------

| Id  | Operation         | Name          | Rows  | Bytes | Cost (%CPU)| Time     |

-----------------------------------------------------------------------------------

|   0 | SELECT STATEMENT  |               |     1 |     4 |     1   (0)| 00:00:01 |

|*  1 |  INDEX UNIQUE SCAN| SYS_C00100786 |     1 |     4 |     1   (0)| 00:00:01 |

-----------------------------------------------------------------------------------

Predicate Information (identified by operation id):

---------------------------------------------------

   1 - access("ID"=TO_NUMBER(:A))