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how to drop all tables in sqlite3 using python?

i made a project which collects data from user and store it on different tables, the application has a delete function which the first option is to delete a specific table which is i already did and the second one is to delete all existing tables.
How can i drop all tables inside my database?
so this is my variables.
conn = sqlite3.connect('main.db')
cursor = conn.execute("DROP TABLE")
cursor.close()

How can i drop all tables inside my database?
According to sqlitetutorial.net
SQLite allows you to drop only one table at a time. To remove multiple
tables, you need to issue multiple DROP TABLE statements.

You can do it by querying all table names (https://www.sqlite.org/faq.html#q7)
Then you can use the result to delete the tables one by one
Here is the code, the function delete_all_tables does that
TABLE_PARAMETER = "{TABLE_PARAMETER}"
DROP_TABLE_SQL = f"DROP TABLE {TABLE_PARAMETER};"
GET_TABLES_SQL = "SELECT name FROM sqlite_schema WHERE type='table';"
def delete_all_tables(con):
tables = get_tables(con)
delete_tables(con, tables)
def get_tables(con):
cur = con.cursor()
cur.execute(GET_TABLES_SQL)
tables = cur.fetchall()
cur.close()
return tables
def delete_tables(con, tables):
cur = con.cursor()
for table, in tables:
sql = DROP_TABLE_SQL.replace(TABLE_PARAMETER, table)
cur.execute(sql)
cur.close()

SQLite3 code to issue multiple DROP TABLE statements based on TEMP_% name wildcard:
.output droptables.sql
SELECT "DROP TABLE """|| sqlite_master.name ||""";" FROM sqlite_master
WHERE type = "table" AND sqlite_master.name LIKE 'TEMP_%';
.read droptables.sql
Example result in .sql output file:
DROP TABLE "TEMP_table1";
DROP TABLE "TEMP_table2";
DROP TABLE "TEMP_table3";
...
Python3 to paste SQL into:
conn = sqlite3.connect(f"main.db")
conn.row_factory = sqlite3.Row
dbc = conn.cursor()
dbc.execute(
f"DROP TABLE 'TEMP_table1';"
)
conn.commit()

Not able to insert into mysql database

I have just started using MySQLdb in python. I am able to create table but when I try to insert, no rows are inserted into the table and its shows that table is still empty.
import MySQLdb
db = MySQLdb.connect("localhost","root","shivam","test")
cursor = db.cursor()
s = "DROP TABLE IF EXISTS batting"
cursor.execute(s)
s = """create table batting (
name varchar(50) primary key,
matches integer(5),
innings integer(5),
runs integer(5),
highest integer(3),
strikerate integer(3),
hundreds integer(3),
fifties integer(3)
)"""
cursor.execute(s)
s = """insert into batting(name) values(
"shivam")"""
cursor.execute(s)
db.close()
Where I could be going wrong?

You forgot to commit your connection. Simply add:
cursor.execute(s)
db.commit()
Have a look at this. It explains why you need to commit

Why doesn't the record get saved in sqlite3?

I am using sqlite for the first time. I used Xammp before. Now I have a scene here. Each time I run the code below, records don't just get appended at the end of the table rather the table is created new and thus it's working just like a console.
Can any one tell me what I am doing wrong here?
import sqlite3
db = sqlite3.connect('test.db')
db.row_factory = sqlite3.Row
db.execute('drop table if exists test')
db.execute('create table test (t1 text,i1 text)')
db.execute('insert into test (t1, i1) values (?, ?)',('xyzs','51'))
cursor = db.execute('select * from test')
for row in cursor:
print(row['t1'],row['i1'])

First, you need to execute commands on a cursor and not the connection itself. Second, you need to commit your transactions:
import sqlite3
db = sqlite3.connect('test.db')
db.row_factory = sqlite3.Row
cur = db.cursor() # getting a cursor
cur.execute('drop table if exists test')
cur.execute('create table test (t1 text,i1 text)')
db.commit() # commit the transaction, note commits are done
# at the connection, not on the cursor
cur.execute('insert into test (t1, i1) values (?, ?)',('xyzs','51'))
db.commit()
cursor = cur.execute('select * from test')
for row in cursor:
print(row['t1'],row['i1'])
Please have a look at the documentation. This will help you once you start working with other databases in Python because they all follow the same API.

This line drops the old table:
db.execute('drop table if exists test')
And this one creates a new table:
db.execute('create table test (t1 text,i1 text)')
That should explain your problem. Remove these two lines and you'll be fine - But create the table first separately.

Python write to MySQL - no error but no writing

I am trying to write into my localhost MySQL database.
I have created a database named "test", a table called "price_update" and a row called "model"
When I run the script below I get no errors, however, I also get nothing written to my database.
I am not sure where to start looking for the problem. the row is varchar(10) and collation utf9_general_ci.
import MySQLdb
conn = MySQLdb.connect(host="127.0.0.1",user="someUser",passwd="somePassword",db="test")
query = "INSERT INTO price_update (model) values ('12345')"
x = conn.cursor()
x.execute(query)
row = x.fetchall()

You have to commit the changes:
conn.commit()
Also, I'd make your query safer:
query = "INSERT INTO price_update (model) values (%s)"
...
x.execute(query, ('12345',))

Postgresql table update

I updated a database table using postgresql from python
My code was
import psycopg2
connection=psycopg2.connect("dbname=homedb user=ria")
cursor=connection.cursor()
l_dict= {'licence_id':1}
cursor.execute("SELECT * FROM im_entry.usr_table")
rows=cursor.fetchall()
for row in rows:
i=i+1
p = findmax(row)
#print p
idn="id"
idn=idn+str(i)
cursor.execute("UPDATE im_entry.pr_table SET (selected_entry) = ('"+p+"') WHERE image_1d ='"+idn+"'")
print 'DATABASE TO PRINT'
cursor.execute("SELECT * FROM im_entry.pr_table")
rows=cursor.fetchall()
for row in rows:
print row
I got the updated table displayed
But when i display updated table by psql as
homedb=# SELECT * FROM im_entry.pr_table;
i got an empty table displayed..what is wrong?? please help me

You're probably not committing the transaction, i.e. you need a connection.commit() after all your updates.
There are various different settings you can make to the isolation level, e.g. autocommit, so you don't need to issue commits yourself. See, for example, How do I do database transactions with psycopg2/python db api?