SQL & PL/SQL

I want SQL queries for these two scenarios

Q. 1) Anagrams of a string i.e. let a name is RAMESH. So all combinations of letters of word RAMESH.
Probably a procedure needs to be written for this eg RAMESH, RHSEMA. There will be 6*5*4*3*2*1 combinations

Q.2 ) There is one table PERSON as follows:

"""
Decision Tree Algorithm in Spark SQL
Written JP Vijaykumar
Date Sep 14 2020

This script is provided for educational purpose only.
Pls modify/change the script as may be required to suit your environment.

I presented a script to process decision tree algorithm using pl/sql earlier.
I like spark sql for the following reasons:
01) It is open source.
02) It combines the rich functionality of python and sql
03) It has the datamining libraries.
04) can be installed on my desktop and play around.

Recently I've been working on tuning some distributed queries. This is not always straightforward.

TIME SERIES ANALYSIS IN SQL AND PL/SQL
Written JP Vijaykumar
Date Mar 8th 2020

From the below table example, I'm trying to identify only the records where VAL_IN changed. So I need to see only 4 records in the below example.
I've been reading about LEAD / LAG and think this is probably the function I need to use, but have not had luck with returning results. Can someone please help push me in the right direction.

Good afternoon people!

I have a procedure in Oracle with various functions of calculations, type simulator. So, I want to assemble a type with output parameters reading this data and bring the results of these functions in real time, because I want to display them as output lines on a front (web screen). I already created the types objects and table. However, I am having difficulty assembling, because I do not know well Type. Can someone help me? Thanks

Decision Tree Algorithm in pl/sql
Author JP Vijaykumar
Date Sept 14th 2019

SELECT tablespace_name ,round(TOTAL_SIZE,2) ,round(TOTAL_SIZE-FREE_SIZE,2) ,
round(FREE_SIZE,2)
FROM (SELECT tablespace_name,(SELECT SUM(BYTES)/1024/1024/1024 FROM DBA_DATA_FILES b WHERE b.TABLESPACE_NAME=a.TABLESPACE_NAME)TOTAL_SIZE,
SUM(bytes)/1024/1024/1024
FREE_SIZE
FROM DBA_FREE_SPACE a GROUP BY tablespace_name) order by 1;

Tablespace Capacity Planning Report
Author JP Vijaykumar
Written Sep 14 2017
Modified Mar 08 2019
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This script is provided for enducational purpose only.
The readers are advised to make necessary changes to the script as may be required for their use in their repective environments.
Pls test this script thoroughly in a lower environment, before using in any production db.

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APRIORI ALGORITHM
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Modified March 08 2019