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Issue while trying to select record in mysql using Python

Error Message
You have an error in your SQL syntax; check the manual that
corresponds to your MariaDB server version for the right syntax to use
near '%s' at line 1
MySQL Database Table
CREATE TABLE `tblorders` (
`order_id` int(11) NOT NULL,
`order_date` date NOT NULL,
`order_number` varchar(50) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
ALTER TABLE `tblorders`
ADD PRIMARY KEY (`order_id`),
ADD UNIQUE KEY `order_number` (`order_number`);
ALTER TABLE `tblorders`
MODIFY `order_id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=4;
Code
mydb = mysql.connector.connect(host = "localhost", user = "root", password = "", database = "mydb")
mycursor = mydb.cursor()
sql = "Select order_id from tblorders where order_number=%s"
val = ("1221212")
mycursor.execute(sql, val)
Am I missing anything?

You must pass a list or a tuple as the arguments, but a tuple of a single value is just a scalar in parentheses.
Here are some workarounds to ensure that val is interpreted as a tuple or a list:
sql = "Select order_id from tblorders where order_number=%s"
val = ("1221212",)
mycursor.execute(sql, val)
sql = "Select order_id from tblorders where order_number=%s"
val = ["1221212"]
mycursor.execute(sql, val)
This is a thing about Python that I always find weird, but it makes a kind of sense.

In case you want to insert data you have to modify your SQL. Use INSERT instead of SELECT like this:
INSERT INTO tblorders (order_number) VALUES ("122121");
That statement will add new record to the table. Besides, in MariaDB you need to use ? instead of %s that works on Mysql database.
sql = "INSERT INTO tblorders (order_number) VALUES (?);"
val = "1231231"
mycursor.execute(sql, [val])

How to leave the unnecessary quotation marks when i convert a csv into a mysqldb with python?

I've got a CSV excel file, which one I want to convert into mysqldb.
It is working very fine, but in every cell in the MYSQLdb there are unnecessary quotation marks, like this: "".
When the cell is empty I see this: ""
When the cell is not empty is see this: "somethingdata"
I can't understand, why put these quotation marks when in the csv file there are none.
Here my code, I think it is correct too.
connection = MySQLdb.connect(host='localhost',
user='root',
passwd='1234',
db='database')
cursor = connection.cursor()
query = """
CREATE TABLE `test` (
`Megnevezes` varchar(100) DEFAULT NULL,
`2015` varchar(100) DEFAULT NULL,
`2014` varchar(100) DEFAULT NULL,
`2013` varchar(100) DEFAULT NULL,
`2012` varchar(100) DEFAULT NULL,
`2011` varchar(100) DEFAULT NULL,
`ID` int(10) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=32 DEFAULT CHARSET=utf8"""
cursor.execute(query)
connection.commit()
cursor.close()
connection = MySQLdb.connect(host='localhost',
user='root',
passwd='1234',
db='database')
cursor = connection.cursor()
query = """ load data local infile 'C:/Python27/output.csv'
into table test
character set latin1
fields terminated by ';'
lines terminated by '\n'
ignore 1 lines;
"""
cursor.execute(query)
connection.commit()
cursor.close()
Any ideas how can I fix this issue?

https://dev.mysql.com/doc/refman/5.7/en/load-data.html
Use the: ENCLOSED BY 'char' where char will be "

Python Iterate through list of dictionaries and save to db

Im new to python and trying to save raw post data in python into mysql.
I want to iterate over each element in the json that is posted and save all the data to DB.
json list of objects: (30 objects with each 11 columns)
[
{
"col1":7878,
"col2":"c004979d3969a86a8fdcda2f92eb39e3",
"col3":"b000yht23",
...
"col11":2
},
{
"col1":7878,
"col2":"c004979d3969a86a8fdcda2f92eb39e3",
"col3":"b000yht23"
...
"col11":43
},
#upto 30 objects
....
]
'json_test' table desc:
CREATE TABLE json_test (
`col1` varchar(250) NOT NULL,
`col2` varchar(250) NOT NULL,
`col3` varchar(250) NOT NULL,
`col4` varchar(250) NOT NULL,
`col5` varchar(250) NOT NULL,
`col6` varchar(250) NOT NULL,
`col7` varchar(250) NOT NULL,
`col8` varchar(250) NOT NULL,
`col9` varchar(250) NOT NULL,
`col10` varchar(250) NOT NULL,
`col11` varchar(200) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
UPDATED to save data to DB:
My py code looks like:
from flask import Flask, abort, request
import json
import pymysql
app = Flask(__name__)
#app.route('/foo', methods=['GET','POST'])
def foo():
jsonobject=request.json
if not jsonobject:
abort(400)
# load- converts JSON source text to a Python value
#readable_json=json.dumps(jsonobject)
#UPDATED with column_names
k=0
for i in jsonobject:
# Connect to the database
conn = pymysql.connect(host='10.20.3.4', port=3306, user='root', passwd='', db='python_db')
try:
with conn.cursor() as cursor:
column_names = ['col1','col2','col3',...'col11']
column_names_str = ', '.join(column_names)
binds_str = ', '.join('%s' for _ in range(len(column_names)))
sql=("INSERT INTO `json_test` ({column_names})" \
" VALUES({binds})"
.format(column_names=column_names_str,binds=binds_str))
for data_dict in jsonobject:
values = [data_dict[column_name]
for column_name in column_names]
cursor.execute(sql, values)
print("Insert successfull!")
#UPDATED
k+=1
conn.commit()
finally:
conn.close()
return "Insert successful"
#return json.dumps(jsonobject)
if __name__ == '__main__':
app.run(host='10.22.1.168',debug=True,port=7845)
UPDATED code result:
Only the last record seems to be inserting

Replace this mess
#UPDATED with column_names
k=0
for i in jsonobject:
# Connect to the database
conn = pymysql.connect(host='10.20.3.4', port=3306, user='root', passwd='', db='python_db')
try:
with conn.cursor() as cursor:
column_names = ['col1','col2','col3',...'col11']
column_names_str = ', '.join(column_names)
binds_str = ', '.join('%s' for _ in range(len(column_names)))
sql=("INSERT INTO `json_test` ({column_names})" \
" VALUES({binds})"
.format(column_names=column_names_str,binds=binds_str))
for data_dict in jsonobject:
values = [data_dict[column_name]
for column_name in column_names]
cursor.execute(sql, values)
print("Insert successfull!")
#UPDATED
k+=1
conn.commit()
finally:
conn.close()
return "Insert successful"
with
try:
with conn.cursor() as cursor:
columns_names = ['col1', 'col2', 'col3', 'col4', 'col5', 'col6',
'col7', 'col8', 'col9', 'col10', 'col11']
columns_names_str = ', '.join(columns_names)
binds_str = ', '.join('%s' for _ in range(len(columns_names)))
for data_dict in jsonobject:
sql = ("INSERT INTO json_test ({columns_names}) "
"VALUES ({binds})"
.format(columns_names=columns_names_str,
binds=binds_str))
values = [data_dict[column_name]
for column_name in columns_names]
cursor.execute(sql, values)
print("Insert successfull!")
conn.commit()
finally:
conn.close()
Summation
k object is redundant,
also name i is unclear and makes me think like it is some kind of index when it is not: it is a dict object,
we don't need to create connection for each object from jsonobject because it is an expensive operation,
we don't need to create sql object on each iteration as well (it remains unchanged),
storing columns names in list/tuple will save us from writing them twice: in a query and in values extraction.
creating binds str
%s, %s, ...
dynamically based on number of columns saves us from typo when we've missed/added too many bind aliases

json.dumps does the opposite of what you claim; it converts a Python object into a string.
The result of request.json is already a Python datastructure. You don't need to do anything else with it.

MySQL + Python : Wrong number of arguments during string formatting

I am executing below query in python to insert data:
query = "INSERT INTO tweetMelbourne(created_at,geo_coordinates_latitude,geo_coordinates_longitude,user_id,polarity_score)" \
"VALUES(?,?,?,?,?)"
args = (created_at,geo_coordinates_latitude,geo_coordinates_longitude,user_id,polarity_score)
try:
cursor = conn.cursor()
cursor.execute(query, args)
But its giving error: Wrong number of arguments during string
formatting
My MySQL table is like this:
CREATE TABLE tweetMelbourne (
`created_at` DATETIME NOT NULL ,
`geo_coordinates_latitude` decimal(12,9) DEFAULT NULL,
`geo_coordinates_longitude` decimal(12,9) DEFAULT NULL,
`user_id` INT,
`polarity_score` INT
)DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;

Python MySql query silently failing

I've got a MySql database (running using the stock Docker image) and it contains a table defined like this:
CREATE TABLE `Edits` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`context` varchar(255) NOT NULL,
`field` varchar(255) NOT NULL,
`value` text,
`username` varchar(255) DEFAULT NULL,
`requested` datetime DEFAULT NULL,
PRIMARY KEY (`id`,`context`,`field`)
) ENGINE=InnoDB AUTO_INCREMENT=15 DEFAULT CHARSET=latin1
I'm connecting to it in a WSGI application, and my connection code looks like this:
import contextlib
import MySQLdb
mysql = MySQLdb.connect(host = 'host', db = 'db')
def _cursor():
mysql.ping(True)
return contextlib.closing(mysql.cursor())
def _exec(sql, params = None):
with _cursor() as c:
c.execute(sql, params)
def save_edits(id, context, field, value, username):
return _exec('REPLACE INTO Edits SET id = %(id)s, context = %(context)s,
field = %(field)s, value = %(value)s, username = %(username)s,
requested = UTC_TIMESTAMP()', {
'id': id,
'context': context,
'field': field,
'value': value,
'username': username,
})
When I call the save_edits function, it doesn't throw an exception, but it fails to update the database. Furthermore, attempting to run the query REPLACE INTO Edits SET id = 1, context = 'x', field = 'y', value = 'z', username = 'foo', requested = UTC_TIMESTAMP(); through a mysql shell afterwards fails with an ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction error. If I wait about 5 minutes, however, that error goes away and I can run the REPLACE INTO query against the MySql database again.
What's going on? How can I fix this error?

It turns out that autocommit is false by default, and closing the cursor without closing the connection will keep the transaction open. I changed the method to:
def _exec(sql, params = None):
with _cursor() as c:
c.execute(sql, params)
mysql.commit()
And that fixed the problem.