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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()

Python Script for sqlite3 can't create table

import sqlite3
conn = sqlite3.connect('serpin.db')
c = conn.cursor()
c.execute("""CREATE TABLE Gene(Gene_name TEXT, Organism TEXT, link_2_gene_with_ID TEXT, Number_SpliceForm INTEGER,ID_mRNA INTEGER, ID_Prt INTEGER);""")
c.execute(".import practice.csv Gene --csv")
c.execute(".mode column")
c.execute("select * from Gene;")
print(c.fetchall())
conn.commit()
conn.close
I can run all these commands individually on my own on the windows terminal in sqlite3. However I get multiple errors running this code, which is roughly what i used in a bash script where i got no errors. The first error I receive is an error that ssays "table Gene already exists." Now even if i comment out that line, i also get an error in the import command, where it says there is a syntax error with the period right before import. These are all sqlite3.OperationalError. I have tried running these commands on their own directly in sqlite3 and have no issues, so i'm not sure what the problem is.
I have no database in this folder, so I'm not sure how the table is already made.
edit(solution): the output of this is not formatted correctly, but this runs without errors.
import csv,sqlite3
conn = sqlite3.connect('serpin.db')
c = conn.cursor()
try:
c.execute("""CREATE TABLE Gene (Gene_name TEXT, Organism TEXT, link_2_gene_with_ID TEXT, Number_SpliceForm INTEGER,ID_mRNA INTEGER, ID_Prt INTEGER);""")
except:
pass
path = r'C:\Users\User\Desktop\sqlite\practice.csv'
with open(path,'r') as fin: # `with` statement available in 2.5+
# csv.DictReader uses first line in file for column headings by default
dr = csv.DictReader(fin) # comma is default delimiter
to_db = [(i['Gene_name'], i['Organism'],i['link_2_gene_with_ID'],i['Number_SpliceForm'],i['ID_mRNA'],i['ID_Prt'] ) for i in dr]
c.executemany("INSERT INTO Gene (Gene_name,Organism,link_2_gene_with_ID,Number_SpliceForm,ID_mRNA,ID_Prt) VALUES (?,?,?,?,?,?);", to_db)
c.execute("select * from Gene;")
print(c.fetchall())
conn.commit()
conn.close

About the fact that you may already have created the table and that gives you an error:
try:
c.execute("""CREATE TABLE Gene(Gene_name TEXT, Organism TEXT, link_2_gene_with_ID TEXT, Number_SpliceForm INTEGER,ID_mRNA INTEGER, ID_Prt INTEGER);""")
except:
pass
To import the file, I report here from another answer from the user mechanical_meat
Importing a CSV file into a sqlite3 database table using Python:
import csv, sqlite3
con = sqlite3.connect(":memory:") # change to 'sqlite:///your_filename.db'
cur = con.cursor()
cur.execute("CREATE TABLE t (col1, col2);") # use your column names here
with open('data.csv','r') as fin: # `with` statement available in 2.5+
# csv.DictReader uses first line in file for column headings by default
dr = csv.DictReader(fin) # comma is default delimiter
to_db = [(i['col1'], i['col2']) for i in dr]
cur.executemany("INSERT INTO t (col1, col2) VALUES (?, ?);", to_db)
con.commit()
con.close()
Don't know about the .mode command, but as far as I know, operation in SQLite3 in python are all in capital letters, thus also select should be SELECT

why the select query through python throwing syntax error?

I am trying to connect to a Postgres DB and execute a simple select query. But I am getting errors. Below is the sample program
import psycopg2 as ps
param_dic = ps.connect(
host="localhost",
database="Test_DB",
user="username",
password="password"
)
cur = param_dic.cursor()
cur.execute("select * from <schema_name>.'employee_tbl'") # I am
rows = cur.fetchall()
for r in rows:
print(r)
I get below error:
psycopg2.errors.SyntaxError: syntax error at or near "'tbl_name'"
LINE 1: select * from <schema_name>.'tbl_name'
If I use
cur.execute("select * from <schema_name>.'Employee_TBL'")
Still, I get the same error.
Note: when I check my pgAdmin, I see below as the table name
<schema_name>.Employee_TBL
So, what is the right way to execute SQL queries on a Postgres table?

replace <schema_name>.'Employee_TBL'" with true value :
dbo.Employee_TBL or another schema name in your database

Maybe it's just a typo, use double quotes for the table if you need to.
Single quotes indicate a string literal.
import psycopg2
conn = psycopg2.connect(...)
cur = conn.cursor()
cur.execute('SELECT * FROM public.servers')
print(len(cur.fetchall()))
cur.execute('SELECT * FROM PUBLIC."servers"')
print(len(cur.fetchall()))
Out:
6
6

Try removing quotes around ‘emloyee_tbl’

The overriding issue is that you created a table name with quoted mixed case. This means that from then on you need to quote the name to be able to use it:
create table "Mixed_Case" (id int, fld_1 varchar);
select * from mixed_case;
ERROR: relation "mixed_case" does not exist
LINE 1: select * from mixed_case;
select * from "Mixed_Case";
id | fld_1
----+-------
(0 rows)
--NOTE the double quotes.
For more information see 4.1.1. Identifiers and Key Words
For the psycopg2 case:
import psycopg2
con = psycopg2.connect("dbname='test' host='localhost' user='aklaver'")
cur = con.cursor()
# Single quoted
cur.execute("select * from public.'Mixed_Case'")
SyntaxError: syntax error at or near "'Mixed_Case'"
LINE 1: select * from public.'Mixed_Case'
# Identifiers need double quotes
# Changing to double quotes
cur.execute('select * from public."Mixed_Case"')
# No error.
# You can also use Postgres functions
cur.execute("select * from quote_ident('public.Mixed_Case')")
For more on Postgres functions and methods see string functions
Also in psycopg2 there is the sql module that allows you to work with identifiers:
from psycopg2 import sql
sql_str = sql.SQL("select * from public.{}").format(sql.Identifier('Mixed_Case'))
print(sql_str.as_string(con))
select * from public."Mixed_Case"
cur.execute(sql_str)

Psycopg2 can not create table

From Jupiter notebook, I was able to create Database with Psycopg2.
But somehow I was not able to create Table and store element in it.
import psycopg2
from psycopg2.extensions import ISOLATION_LEVEL_AUTOCOMMIT
con = psycopg2.connect("user=postgres password='abc'");
con.set_isolation_level(ISOLATION_LEVEL_AUTOCOMMIT);
cursor = con.cursor();
name_Database = "socialmedia";
sqlCreateDatabase = "create database "+name_Database+";"
cursor.execute(sqlCreateDatabase);
With the above code, I can see database named "socialmedia" from psql (windows command prompt).
But with the below code, I can not see table named "test_table" from psql.
import psycopg2
# Open a DB session
dbSession = psycopg2.connect("dbname='socialmedia' user='postgres' password='abc'");
# Open a database cursor
dbCursor = dbSession.cursor();
# SQL statement to create a table
sqlCreateTable = "CREATE TABLE test_table(id bigint, cityname varchar(128), latitude numeric, longitude numeric);";
# Execute CREATE TABLE command
dbCursor.execute(sqlCreateTable);
# Insert statements
sqlInsertRow1 = "INSERT INTO test_table values(1, 'New York City', 40.73, -73.93)";
sqlInsertRow2 = "INSERT INTO test_table values(2, 'San Francisco', 37.733, -122.446)";
# Insert statement
dbCursor.execute(sqlInsertRow1);
dbCursor.execute(sqlInsertRow2);
# Select statement
sqlSelect = "select * from test_table";
dbCursor.execute(sqlSelect);
rows = dbCursor.fetchall();
# Print rows
for row in rows:
print(row);
I can get elements only from Jupyter notebook, but not from psql.
And it seems elements are stored temporarily.
How can I see table and elements from psql and keep the element permanently?

I don't see any dbCursor.execute('commit') in the second part of your question?
You have provided an example with AUTOCOMMIT which works, and you are asking why results are stored temporarly when you are not using AUTOCOMMIT?
Well, they are not commited!
They are stored only for the current session, that's why you can get it from your Jupyter session
Also:
you don't need to put semicolons in your python code
you don't need to put semicolons in your SQL code (except when you execute multiple statements, which is not the case here)

Load CSV MySQLdb - Python

I have a CSV that I'm attempting to load into a MySQL database. I'm running the following code:
import MySQLdb
con = MySQLdb.connect(host="myhost",
user="me",
passwd="mypw",
db="mydb")
cur = con.cursor()
sqlscript =r"""
DROP TABLE IF EXISTS MyTable;
CREATE TABLE MyTable
(Col1 VARCHAR(255),
Col2 VARCHAR(255),
CONSTRAINT PK_MyTable PRIMARY KEY (Col1));
LOAD DATA LOCAL INFILE 'C:\\Users\\me\\Documents\\Rec\\New Files\\mycsv.csv'
INTO TABLE MyTable
CHARACTER SET UTF8
FIELDS TERMINATED BY ','
ESCAPED BY '!'
ENCLOSED BY '"'
OPTIONALLY ENCLOSED BY '\''
LINES TERMINATED BY '\r\n'
IGNORE 1 LINES;"""
cur.execute(sqlscript)
cur.close()
This runs without error, but does not load data from my CSV file. It correctly drops the table and creates it using the script. When I then query the table, it has zero rows. What am I missing?