Repeat a command while true or x times (equivalent of while/for loop) - sqlite

Question

I would like to repeat this command as many times as there is still sometextin the field note (several rows from the table itemNotes could have one or more sometext in the field note):
UPDATE itemNotes
SET
note = SUBSTR(note, 0, INSTR(LOWER(note), 'sometext')) || 'abc' || SUBSTR(note, INSTR(LOWER(note), 'sometext')+sometext_len)
WHERE
INSTR(LOWER(note), 'sometext') >= 0;
So a proto-code would be :
While (SELECT * FROM itemNotes WHERE note like "%sometext%") >1
UPDATE itemNotes
SET
note = SUBSTR(note, 0, INSTR(LOWER(note), 'sometext')) || 'abc' || SUBSTR(note, INSTR(LOWER(note), 'sometext')+sometext_len)
WHERE
INSTR(LOWER(note), 'sometext') >= 0;
END
But apparently Sqlite3 doesn't support While loop or for loop. They can be emulated with something like this but I have difficulties integrating what I want with this query:
WITH b(x,y) AS
(
SELECT 1,2
UNION ALL
SELECT x+ 1, y + 1
FROM b
WHERE x < 20
) SELECT * FROM b;
Any idea how to do this?
PS: I don't use replace because I want to replace all the case combinations of sometext (e.g. sometext, SOMEtext, SOmeText...) cf this question
Current input and desired output:
For a single row, a note field could look like (and many rows in the table itemNotescould look like this one):
There is SOmetext and also somETExt and more SOMETEXT and even more sometext
The query should output:
There is abc and also abc and more abc and even more abc
I am doing it on the zotero.sqlite, which is created by this file (line 85). The table is created by this query
CREATE TABLE itemNotes (
itemID INTEGER PRIMARY KEY,
parentItemID INT,
note TEXT,
title TEXT,
FOREIGN KEY (itemID) REFERENCES items(itemID) ON DELETE CASCADE,
FOREIGN KEY (parentItemID) REFERENCES items(itemID) ON DELETE CASCADE
);

Answer 1

You just have your answer in your query:
UPDATE itemNotes
SET
note = SUBSTR(note, 0, INSTR(LOWER(note), 'sometext')) || 'abc' || SUBSTR(note, INSTR(LOWER(note), 'sometext')+sometext_len)
WHERE
note LIKE "%sometext%";
It will update all rows that contain sometext in the note field
UPDATE
If you want to update the field which has multiple occurrences in different cases and maintain the rest of the text the simplest solution imo is to use regex and for that you need an extension
UPDATE itemNotes
SET
note = regex_replace('\bsometext\b',note,'abc')
WHERE
note LIKE "%sometext%";

Answer 2

As recommended by Stephan in his last comment, I used python to do this.
Here is my code :
import sqlite3
import re
keyword = "sometext"
replacement = "abc"
db = sqlite3.connect(path_to_sqlite)
cursor = db.cursor()
cursor.execute(f'SELECT * FROM itemNotes WHERE note like "%{keyword}%"')
for row in cursor.fetchall():
row_regex = re.compile(re.escape(keyword), re.IGNORECASE)
row_regex_replaced = row_regex.sub(replacement, row[2])
rowID = row[0]
sql = "REPLACE INTO itemNotes (itemID,note) VALUES (?,?)"
data = (rowID, row_regex_replaced)
cursor.execute(sql, data)
db.commit()