insert into without error but not inserting. + more intuitive syntax? - python

I want to insert data into a table created with SQLite. Most of the code is converting my arrays into one string for con.excute(). Maybe this is the problem? Is there a better way? No error returned.
def add_row(table, columns, values):
con = sql_connection("database.db")
cursorObj = con.cursor()
# column list to string
if isinstance(columns, list) == True:
columns = ", ".join(columns)
# wrap each string in list with '' and convert whole list to string
if isinstance(values, list) == True:
for i in range(0, len(values)):
if isinstance(values[i], str) == True:
values[i] = "'" + values[i] + "'"
values = ", ".join(values)
try:
cmd = "insert into " + table + "(" + columns + ") values (" + values + ")"
print(cmd)
cursorObj.execute(cmd)
except sqlite3.Error as e:
print("An error occurred:", e.args[0])
add_row("Stocks", ["symbol", "name"], ["TEST", "test"])
print(cmd) output:
insert into Stocks (symbol, name) values ('TEST', 'test')
CLARIFICATION: I'm not worried about security concerns. It will only ever be used locally.

I don't recommend trying to generalize this function for arbitrary tables and columns.
def add_symbol_and_name(symbol, name):
with sqlite3.connect("database.db") as con:
cursor = con.cursor()
cursor.execute("insert into Stocks (symbol, name) values (?, ?)",
(symbol, name))
Anything more dynamic than this opens you up to SQL injection attacks.

I figured it out. Note what others have said: such a general function should not be used online as makes the database vulnerable to SQL injection attacks. However, my database is, and will always be, local.
def add_row(table, columns, values):
valueArr = []
if (len(columns) == len(values)) == False:
print("Values and columns must be of equal length")
return
columns = ", ".join(columns)
for value in values:
valueArr.append("?")
valueArr = ", ".join(valueArr)
with sqlite3.connect("database.db") as con:
try:
cursor = con.cursor()
cmd = "insert into " + table + " (" + columns + ") values (" + valueArr + ")"
print("cmd", cmd)
cursor.execute(cmd,
values)
except sqlite3.Error as e:
print("An error occurred:", e.args[0])
add_row("Stocks", ["symbol", "name", "exchange"], ["AAPL", "Apple", "NASDAQ"])

Related

I am using Flask and MySQL database but the update query is giving error [duplicate]

I have multiple tables that are updated after a value is changed in a grid. These tables don't always have the same keys or columns so I cannot explicitly name the columns or formats. The only thing that is ever the same, is the column where the keys reside. I know the way I am currently doing this is not correct and leaves me open to injection attacks.
I also ran into an issue where some of the values contain keys that throw an error in the SQL statement. For example, updating WHERE email = t'est#email.com.
I am not really sure of the proper way to write these statements. I did some research and see multiple methods for different purposes but am not sure which is proper. I am looking to do this as dynamically as possible. Can anyone point me in the right direction?
To connect:
import mysql.connector as sql
import MySQLdb
#Connect
self.db_name = 'database'
self.server = 'server'
self.user_id = 'user'
self.pw = 'password'
try:
self.db_con = MySQLdb.connect(user=self.user_id,password=self.pw,database=self.db_name,
host=self.server,charset='utf8',autocommit=True)
self.cursor = self.db_con.cursor()
except:
print("Error connecting")
SQL Statements:
key_id = str("'") + self.GetCellValue(event.GetRow(),1) + str("'")
target_col = self.GetColLabelValue(event.GetCol())
key_col = self.GetColLabelValue(1)
nVal = str("'") + self.GetCellValue(event.GetRow(),event.GetCol()) + str("'")
#SQL STATEMENTS
sql_update = "UPDATE " + tbl + " SET " + target_col + " = " + nVal + " WHERE " + key_col + " = " + key_id + ""
#INSERT
sql_update = ("INSERT INTO " + str(self.tbl) + "(" + self.key_col + ")" + "VALUES (" + str("'") + str(val) + str("'") + ")")
#DELETE
sql_update = "DELETE FROM " + tbl + " WHERE " + self.key_col + " = " + self.key_id + ""
#SELECT
sql_query = "SELECT * FROM " + self.tbl
#Excecute
try:
self.cursor.execute(sql_update)
except:
print('Error')
self.db_con.rollback()
Databases have different notations for "quoting" identifiers (table and column names etc) and values (data).
MySQL uses backticks to quote identifiers. For values, it's best to use the parameter substitution mechanism provided by the connector package: it's more likely to handle tricky cases like embedded quotes correctly, and will reduce the risk of SQL injection.
Here's an example for inserts; the same techniques can be used for the other types of query.
key_id = str("'") + self.GetCellValue(event.GetRow(),1) + str("'")
target_col = self.GetColLabelValue(event.GetCol())
key_col = self.GetColLabelValue(1)
nVal = str("'") + self.GetCellValue(event.GetRow(),event.GetCol()) + str("'")
#INSERT (using f-strings for brevity)
sql_update = (f"INSERT INTO `{self.tbl}` (`{self.key_col}`) VALUES (%s)")
# Pass the statement and values to cursor.execute.
# The values are assumed to be a sequence, so a single value should be
# placed in a tuple or list.
self.cursor.execute(sql_update, (nVal,))
If you have more than one column / value pair you could do something like this:
cols = ['A', 'B', 'C']
vals = ['a', 'b', 'c']
col_names = ','.join([f'`{c}`' for c in cols])
values_placeholder = ','.join(['%s'] * len(cols))
sql_update = (f"INSERT INTO `{self.tbl}` (col_names) VALUES ({values_placeholder})")
self.cursor.execute(sql_update, vals)
Values are not only data for insertion, but also data that we are using for comparison, for example in WHERE clauses. So an update statement with a filter might be created like this:
sql_update = (f"UPDATE `{tbl}` SET (`{target_col}`) = (%s) WHERE (`{key_col}`) = %s")
self.cursor.execute(sql_update, (nVal, key_id))
However sometimes the target of a SET or WHERE clause may be a column, for example we want to do an update based on other values in the row. For example, this statement will set target_col to the value of other_col for all rows where key_col is equal to other_key_col:
sql_update = (f"UPDATE `{tbl}` SET (`{target_col}`) = `{other_col}` WHERE (`{key_col}`) = `{other_key_col}`")
self.cursor.execute(sql_update)

Dynamic SQL Queries with Python and mySQL

I have multiple tables that are updated after a value is changed in a grid. These tables don't always have the same keys or columns so I cannot explicitly name the columns or formats. The only thing that is ever the same, is the column where the keys reside. I know the way I am currently doing this is not correct and leaves me open to injection attacks.
I also ran into an issue where some of the values contain keys that throw an error in the SQL statement. For example, updating WHERE email = t'est#email.com.
I am not really sure of the proper way to write these statements. I did some research and see multiple methods for different purposes but am not sure which is proper. I am looking to do this as dynamically as possible. Can anyone point me in the right direction?
To connect:
import mysql.connector as sql
import MySQLdb
#Connect
self.db_name = 'database'
self.server = 'server'
self.user_id = 'user'
self.pw = 'password'
try:
self.db_con = MySQLdb.connect(user=self.user_id,password=self.pw,database=self.db_name,
host=self.server,charset='utf8',autocommit=True)
self.cursor = self.db_con.cursor()
except:
print("Error connecting")
SQL Statements:
key_id = str("'") + self.GetCellValue(event.GetRow(),1) + str("'")
target_col = self.GetColLabelValue(event.GetCol())
key_col = self.GetColLabelValue(1)
nVal = str("'") + self.GetCellValue(event.GetRow(),event.GetCol()) + str("'")
#SQL STATEMENTS
sql_update = "UPDATE " + tbl + " SET " + target_col + " = " + nVal + " WHERE " + key_col + " = " + key_id + ""
#INSERT
sql_update = ("INSERT INTO " + str(self.tbl) + "(" + self.key_col + ")" + "VALUES (" + str("'") + str(val) + str("'") + ")")
#DELETE
sql_update = "DELETE FROM " + tbl + " WHERE " + self.key_col + " = " + self.key_id + ""
#SELECT
sql_query = "SELECT * FROM " + self.tbl
#Excecute
try:
self.cursor.execute(sql_update)
except:
print('Error')
self.db_con.rollback()
Databases have different notations for "quoting" identifiers (table and column names etc) and values (data).
MySQL uses backticks to quote identifiers. For values, it's best to use the parameter substitution mechanism provided by the connector package: it's more likely to handle tricky cases like embedded quotes correctly, and will reduce the risk of SQL injection.
Here's an example for inserts; the same techniques can be used for the other types of query.
key_id = str("'") + self.GetCellValue(event.GetRow(),1) + str("'")
target_col = self.GetColLabelValue(event.GetCol())
key_col = self.GetColLabelValue(1)
nVal = str("'") + self.GetCellValue(event.GetRow(),event.GetCol()) + str("'")
#INSERT (using f-strings for brevity)
sql_update = (f"INSERT INTO `{self.tbl}` (`{self.key_col}`) VALUES (%s)")
# Pass the statement and values to cursor.execute.
# The values are assumed to be a sequence, so a single value should be
# placed in a tuple or list.
self.cursor.execute(sql_update, (nVal,))
If you have more than one column / value pair you could do something like this:
cols = ['A', 'B', 'C']
vals = ['a', 'b', 'c']
col_names = ','.join([f'`{c}`' for c in cols])
values_placeholder = ','.join(['%s'] * len(cols))
sql_update = (f"INSERT INTO `{self.tbl}` (col_names) VALUES ({values_placeholder})")
self.cursor.execute(sql_update, vals)
Values are not only data for insertion, but also data that we are using for comparison, for example in WHERE clauses. So an update statement with a filter might be created like this:
sql_update = (f"UPDATE `{tbl}` SET (`{target_col}`) = (%s) WHERE (`{key_col}`) = %s")
self.cursor.execute(sql_update, (nVal, key_id))
However sometimes the target of a SET or WHERE clause may be a column, for example we want to do an update based on other values in the row. For example, this statement will set target_col to the value of other_col for all rows where key_col is equal to other_key_col:
sql_update = (f"UPDATE `{tbl}` SET (`{target_col}`) = `{other_col}` WHERE (`{key_col}`) = `{other_key_col}`")
self.cursor.execute(sql_update)

Why Does Empty MySQL Database Claim to Have Duplicates (Python 3)?

So I have a quick function that's supposed to upload data (stored in a Python dictionary) to a MySQL database.
def uploadData(of_item):
global DB_HOST
global DB_USER
global DB_PASSWORD
global DB_DATABASE
my_db = connector.connect(host=DB_HOST, user=DB_USER, passwd=DB_PASSWORD, database=DB_DATABASE, port=3306)
my_db.autocommit = True
my_cursor = my_db.cursor()
print("\rThe DB pipeline is now connected.")
slots_text = ", ".join([a[0] for a in of_item.items()])
values_text = ", ".join(["'" + a[1].replace("'", "\\'") + "'" for a in of_item.items()])
set_portion_text = ", ".join([a[0] + " = " + "'" + a[1].replace("'", "\\'") + "'" for a in of_item.items()])
sql = 'INSERT INTO UsersData ({0}) VALUES ({1})'.format(slots_text, values_text)
try:
my_cursor.execute(sql)
row_cnt = my_cursor.rowcount
my_db.commit()
my_cursor.close()
my_db.close()
print("\r" + str(row_cnt) + " is now in UsersData.")
return [True, str(row_cnt)]
except Exception as exception:
print("\n".join(["The update failed for profileID: " + of_item['UniqueId'],
str(exception),
str(sql),
"*",
'Item:',
str(of_item),
"*"]))
my_cursor.close()
my_db.close()
return [False, 0]
Currently, the row_cnt sits at -1, so it should be entirely empty. However, when I execute the function, I'm constantly getting this thrown error:
1062 (23000): Duplicate entry 'ABCDEFGHIJKLMNOPQRSTUVWXYZ-123' for key 'profileId_2'
Now, profileId_2 is just this:
...
UNIQUE KEY `profileId_2` (`profileId`,`companyId`),
...
profileId is whatever the user's unique ID is, and companyId is just a preset (in this case, 123). It's odd that there would be a claimed duplicate, since there's nothing in the database yet.
First, what might be causing this error? Second, how can I get through it and successfully append new entries to UsersData?

Why pymysql not insert record into table?

I am pretty new in python developing. I have a long python script what "clone" a database and add additional stored functions and procedures. Clone means copy only the schema of DB.These steps work fine.
My question is about pymysql insert exection:
I have to copy some table contents into the new DB. I don't get any sql error. If I debug or print the created INSERT INTO command is correct (I've tested it in an sql editor/handler). The insert execution is correct becuse the result contain the exact row number...but all rows are missing from destination table in dest.DB...
(Ofcourse DB_* variables have been definied!)
import pymysql
liveDbConn = pymysql.connect(DB_HOST, DB_USER, DB_PWD, LIVE_DB_NAME)
testDbConn = pymysql.connect(DB_HOST, DB_USER, DB_PWD, TEST_DB_NAME)
tablesForCopy = ['role', 'permission']
for table in tablesForCopy:
with liveDbConn.cursor() as liveCursor:
# Get name of columns
liveCursor.execute("DESCRIBE `%s`;" % (table))
columns = '';
for column in liveCursor.fetchall():
columns += '`' + column[0] + '`,'
columns = columns.strip(',')
# Get and convert values
values = ''
liveCursor.execute("SELECT * FROM `%s`;" % (table))
for result in liveCursor.fetchall():
data = []
for item in result:
if type(item)==type(None):
data.append('NULL')
elif type(item)==type('str'):
data.append("'"+item+"'")
elif type(item)==type(datetime.datetime.now()):
data.append("'"+str(item)+"'")
else: # for numeric values
data.append(str(item))
v = '(' + ', '.join(data) + ')'
values += v + ', '
values = values.strip(', ')
print("### table: %s" % (table))
testDbCursor = testDbConn.cursor()
testDbCursor.execute("INSERT INTO `" + TEST_DB_NAME + "`.`" + table + "` (" + columns + ") VALUES " + values + ";")
print("Result: {}".format(testDbCursor._result.message))
liveDbConn.close()
testDbConn.close()
Result is:
### table: role
Result: b"'Records: 16 Duplicates: 0 Warnings: 0"
### table: permission
Result: b'(Records: 222 Duplicates: 0 Warnings: 0'
What am I doing wrong? Thanks!
You have 2 main issues here:
You don't use conn.commit() (which would be either be liveDbConn.commit() or testDbConn.commit() here). Changes to the database will not be reflected without committing those changes. Note that all changes need committing but SELECT, for example, does not.
Your query is open to SQL Injection. This is a serious problem.
Table names cannot be parameterized, so there's not much we can do about that, but you'll want to parameterize your values. I've made multiple corrections to the code in relation to type checking as well as parameterization.
for table in tablesForCopy:
with liveDbConn.cursor() as liveCursor:
liveCursor.execute("SELECT * FROM `%s`;" % (table))
name_of_columns = [item[0] for item in liveCursor.description]
insert_list = []
for result in liveCursor.fetchall():
data = []
for item in result:
if item is None: # test identity against the None singleton
data.append('NULL')
elif isinstance(item, str): # Use isinstance to check type
data.append(item)
elif isinstance(item, datetime.datetime):
data.append(item.strftime('%Y-%m-%d %H:%M:%S'))
else: # for numeric values
data.append(str(item))
insert_list.append(data)
testDbCursor = testDbConn.cursor()
placeholders = ', '.join(['`%s`' for item in insert_list[0]])
testDbCursor.executemany("INSERT INTO `{}.{}` ({}) VALUES ({})".format(
TEST_DB_NAME,
table,
name_of_columns,
placeholders),
insert_list)
testDbConn.commit()
From this github thread, I notice that executemany does not work as expected in psycopg2; it instead sends each entry as a single query. You'll need to use execute_batch:
from psycopg2.extras import execute_batch
execute_batch(testDbCursor,
"INSERT INTO `{}.{}` ({}) VALUES ({})".format(TEST_DB_NAME,
table,
name_of_columns,
placeholders),
insert_list)
testDbConn.commit()
How to insert data into table using python pymsql
Find my solution below
import pymysql
import datetime
# Create a connection object
dbServerName = "127.0.0.1"
port = 8889
dbUser = "root"
dbPassword = ""
dbName = "blog_flask"
# charSet = "utf8mb4"
conn = pymysql.connect(host=dbServerName, user=dbUser, password=dbPassword,db=dbName, port= port)
try:
# Create a cursor object
cursor = conn.cursor()
# Insert rows into the MySQL Table
now = datetime.datetime.utcnow()
my_datetime = now.strftime('%Y-%m-%d %H:%M:%S')
cursor.execute('INSERT INTO posts (post_id, post_title, post_content, \
filename,post_time) VALUES (%s,%s,%s,%s,%s)',(5,'title2','description2','filename2',my_datetime))
conn.commit()
except Exception as e:
print("Exeception occured:{}".format(e))
finally:
conn.close()

Creating a button to delete data from table in qt

Using mysql and python, I have created a table within PyQt that will allow a user to frequently update and track their meeting sessions. The only problem is, I do not know how I would go about coding a button that will allow me to individually delete a row of data.
My table looks like so:
What would be the simplest way to create a button that will appear besides the row of data when new data is inserted that will allow the user to delete that entire row?
Edit:
def deleteRows(self):
items = self.treeWidget.selectedItems()
current = self.treeWidget.currentItem()
for item in items:
sip.delete(current)
self.UpdateTree()
Edit 2:
import mysql.connector
from mysql.connector import errorcode
from datetime import datetime
class DatabaseUtility:
def __init__(self, database, tableName):
self.db = database
self.tableName = tableName
f = open('C:\\Users\\Vlad\\Desktop\\Myfiles\\EnterprisePassport\\password.txt', 'r')
p = f.read(); f.close();
self.cnx = mysql.connector.connect(user = 'root',
password = p,
host = '127.0.0.1')
self.cursor = self.cnx.cursor()
self.ConnectToDatabase()
self.CreateTable()
def ConnectToDatabase(self):
try:
self.cnx.database = self.db
except mysql.connector.Error as err:
if err.errno == errorcode.ER_BAD_DB_ERROR:
self.CreateDatabase()
self.cnx.database = self.db
else:
print(err.msg)
def CreateDatabase(self):
try:
self.RunCommand("CREATE DATABASE %s DEFAULT CHARACTER SET 'utf8';" %self.db)
except mysql.connector.Error as err:
print("Failed creating database: {}".format(err))
def CreateTable(self):
cmd = (" CREATE TABLE IF NOT EXISTS " + self.tableName + " ("
" `ID` int(5) NOT NULL AUTO_INCREMENT,"
" `date` date NOT NULL,"
" `time` time NOT NULL,"
" `message` char(50) NOT NULL,"
" PRIMARY KEY (`ID`)"
") ENGINE=InnoDB;")
self.RunCommand(cmd)
def GetTable(self):
self.CreateTable()
return self.RunCommand("SELECT * FROM %s;" % self.tableName)
def GetColumns(self):
return self.RunCommand("SHOW COLUMNS FROM %s;" % self.tableName)
def RunCommand(self, cmd):
print ("RUNNING COMMAND: " + cmd)
try:
self.cursor.execute(cmd)
except mysql.connector.Error as err:
print ('ERROR MESSAGE: ' + str(err.msg))
print ('WITH ' + cmd)
try:
msg = self.cursor.fetchall()
except:
msg = self.cursor.fetchone()
return msg
def AddEntryToTable(self, message):
date1 = datetime.now().strftime("%y-%m-%d")
time = datetime.now().strftime("%H:%M")
cmd = " INSERT INTO " + self.tableName + " (date, time, message)"
cmd += " VALUES ('%s', '%s', '%s' );" % (date1, time, message)
self.RunCommand(cmd)
def __del__(self):
self.cnx.commit()
self.cursor.close()
self.cnx.close()
if __name__ == '__main__':
db = 'enterprisepassport'
tableName = 'session'
dbu = DatabaseUtility(db, tableName)
Just add a button at the top that deletes the selected rows. It looks like your using a QTreeWidget
def __init__(...)
...
self.deleteButton.clicked.connect(self.deleteRows)
def deleteRows(self):
items = self.tree.selectedItems()
for item in items:
# Code to delete items in database
self.refreshTable()
#Randomator, why not explain as if you're explaining to a beginner. Even I do not also understand what you're suggesting.
The guy wrote his codes, make corrections in his code so he can easily run the file

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