Oracle 18c

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CREATE OR REPLACE package mytest is
      TYPE MY_TABLE IS TABLE OF VARCHAR2(30);

      FUNCTION mytable_test ( in_param IN MY_TABLE , out_param OUT MY_TABLE , inout_param IN OUT MY_TABLE )
               RETURN MY_TABLE ;
end mytest;
/
SELECT * FROM all_types WHERE OWNER = USER AND TYPE_NAME = 'MY_TABLE';
SELECT * FROM all_plsql_types WHERE OWNER = USER AND TYPE_NAME  = 'MY_TABLE';


OWNER
TYPE_NAME
PACKAGE_NAME
TYPE_OID
TYPECODE
ATTRIBUTES
CONTAINS_PLSQL


FIDDLE_AOTMOHUOLDRSWJJMQTBL
MY_TABLE
MYTEST
0xDBFEF5CFA27847FCE0536D04A8C056EC
COLLECTION
0
NO


SELECT * FROM all_plsql_coll_types WHERE OWNER = USER AND TYPE_NAME  = 'MY_TABLE';


OWNER
TYPE_NAME
PACKAGE_NAME
COLL_TYPE
UPPER_BOUND
ELEM_TYPE_OWNER
ELEM_TYPE_NAME
ELEM_TYPE_PACKAGE
LENGTH
PRECISION
SCALE
CHARACTER_SET_NAME
ELEM_STORAGE
NULLS_STORED
CHAR_USED
INDEX_BY
ELEM_TYPE_MOD


FIDDLE_AOTMOHUOLDRSWJJMQTBL
MY_TABLE
MYTEST
TABLE
null
null
VARCHAR2
null
30
null
null
CHAR_CS
null
YES
B
null
null