sharing tkinter app and using my machine as MySQL server? - python

Hi I have created a tkinter app that uses MySQL database but I have two questions:
when I will share my app with others, will they be able to use MySQL database that I have in my computer? If not, what should I need to change in my code?
after I transform the app to .exe by using pyinstaller, then why I can not send it to others people by gmail?
To connect to my database I used this:
import mysql.connector
db = mysql.connector.connect(
host="localhost",
username = myusername,
password=mypassword,
database = "mydatabase"
)
Thank you so much for any help or answer.

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I've been trying for some days to connect my python 3 script to PostgresSQL database(psycopg2) in Heroku, without Django.
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Articles that I found helpful at the beginning, even if they were not enough:
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Procfile has to be:
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To make sure this was properly set, this was quite helpful.
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postgres://username:password#host:port/database
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postgres://jticiuimwernbk:ff78903549d4c6ec13a53a8ffefcd201b937d54c35d976
#ec2-52-123-182-987.compute-1.amazonaws.com:5432/dbsd4fdf6c1awq
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password = 'ff78903549d4c6ec13a53a8ffefcd201b937d54c35d976'
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user=user,
password=password,
host=host,
port=port)
# and now I was able to perform queries:
cur = conn.cursor()
results = cur.execute("<some SQL query>;").fetchall()
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conn.close()

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