The column `HIGH_VALUE` has data similar to below, of type `LONG`, and always has the same length: 

```
TIMESTAMP' 2019-01-30 00:00:00'

```

How can I convert it to a `DATE` type without using a function?

My overall goal is to create a result set which can then be used as an inner query for other aggregations. For example, I would like to be able to sum the number of rows over a year according to the date produced by converting the `HIGH_VALUE` column to a date. 

I have only read permissions on this database and therefore cannot create functions. I've seen other solutions on StackOverflow and other sites, but they all require creating a function. 

`ALL_TAB_PARTITIONS` is a standard built-in Oracle table and therefore I'm not including the table structure. In case that's an issue, please let me know and I will create an example table. 

An example query and the data one row that results from this query follows. Note that I cannot create tables on this database so I will also need an a method that works without creating a temporary table.

```
Insert into EXPORT_TABLE (TABLE_OWNER,TABLE_NAME,PARTITION_NAME,HIGH_VALUE,NUM_ROWS) 
VALUES ('TO','TN','SYS_P201709','TIMESTAMP'' 2019-01-30 00:00:00''',5053133);

SELECT TABLE_OWNER, TABLE_NAME, PARTITION_NAME, HIGH_VALUE, NUM_ROWS
from ALL_TAB_PARTITIONS;

```