I am using SQLAlchemy and MSSQL. I am simply inserting a row and I would like to get back the id of the newly created record.
The SQL query that works with MSSQL and returns the id is:
INSERT INTO [table](...) OUTPUT inserted.ID VALUES (...)
and the alchemy statement I am using is:
with connection() as conn:
query = ...
result_proxy = conn.execute(query)
If you run the query in a sql console, you get back the ID, but I cannot figure out how to get it from the result_proxy returned by the execute statement.
things I have tried and did not work:
result_proxy.lastrowid
result_proxy.last_inserted_id
result_proxy.fetchone()
result_proxy.fetchall()
You are on the right track. I just tried this and it works for me:
import sqlalchemy as sa
# ...
# set up test environment
with engine.begin() as conn:
conn.exec_driver_sql("DROP TABLE IF EXISTS team")
conn.exec_driver_sql(
"CREATE TABLE team ("
"id int identity primary key, "
"prov nvarchar(5), "
"city nvarchar(50), "
"team_name nvarchar(50)"
")"
)
# perform the test
sql = """\
INSERT INTO team (prov, city, team_name)
OUTPUT inserted.id
VALUES (:prov, :city, :team_name)
"""
with engine.begin() as conn:
new_id = conn.execute(
sa.text(sql),
{"prov": "AB", "city": "Calgary", "team_name": "Flames"}
).scalar()
print(new_id) # 1
Related
I'm aware that the best way to prevent sql injection is to write Python queries of this form (or similar):
query = 'SELECT %s %s from TABLE'
fields = ['ID', 'NAME']
cur.execute(query, fields)
The above will work for a single query, but what if we want to do a UNION of 2 SQL commands? I've set this up via sqlite3 for sake of repeatability, though technically I'm using pymysql. Looks as follows:
import sqlite3
conn = sqlite3.connect('dummy.db')
cur = conn.cursor()
query = 'CREATE TABLE DUMMY(ID int AUTO INCREMENT, VALUE varchar(255))'
query2 = 'CREATE TABLE DUMMy2(ID int AUTO INCREMENT, VALUE varchar(255)'
try:
cur.execute(query)
cur.execute(query2)
except:
print('Already made table!')
tnames = ['DUMMY1', 'DUMMY2']
sqlcmds = []
for i in range(0,2):
query = 'SELECT %s FROM {}'.format(tnames[i])
sqlcmds.append(query)
fields = ['VALUE', 'VALUE']
sqlcmd = ' UNION '.join(sqlcmds)
cur.execute(sqlcmd, valid_fields)
When I run this, I get a sqlite Operational Error:
sqlite3.OperationalError: near "%": syntax error
I've validated the query prints as expected with this output:
INSERT INTO DUMMY VALUES(%s) UNION INSERT INTO DUMMY VALUES(%s)
All looks good there. What is the issue with the string substitutions here? I can confirm that running a query with direct string substitution works fine. I've tried it with both selects and inserts.
EDIT: I'm aware there are multiple ways to do this with executemany and a few other. I need to do this with UNION for the purposes I'm using this for because this is a very, very simplified example fo the operational code I'm using
The code below executes few INSERTS at once
import sqlite3
conn = sqlite3.connect('dummy.db')
cur = conn.cursor()
query = 'CREATE TABLE DUMMY(ID int AUTO INCREMENT NOT NULL, VALUE varchar(255))'
try:
cur.execute(query)
except:
print('Already made table!')
valid_fields = [('ya dummy',), ('stupid test example',)]
cur.executemany('INSERT INTO DUMMY (VALUE) VALUES (?)',valid_fields)
I have an issue to run my SQL queries on a Postgres ElephantSql hosted:
This is my code to connect (except dynamo, user, password which are replaced by XXX
DATABASE_URL = 'postgres://YYYY:ZZZZ#drona.db.elephantsql.com:5432/YYYY'
# ---------------------------- CONNECT ELEPHANT DB
def ElephantConnect():
up.uses_netloc.append("postgres")
url = up.urlparse(DATABASE_URL)
conn = psycopg2.connect(dbname='YYYY',
user='YYYY',
password='ZZZZ',
host='drona.db.elephantsql.com',
port='5432'
)
cursor = conn.cursor()
# cursor.execute("CREATE TABLE notes(id integer primary key, body text, title text);")
#conn.commit()
# conn.close()
return conn
this code seems to connect well to db
My issue is when I want to delete a table:
def update(df, table_name, deleteYes= 'Yes'):
conn = ElephantConnect()
db = create_engine(DATABASE_URL)
cursor =conn.cursor()
if deleteYes == 'Yes': # delete
queryCount = "SELECT count(*) FROM {};".format(table_name)
queryDelete = "DELETE FROM {};".format(table_name)
count = db.execute(queryCount)
rows_before = count.fetchone()[0]
try:
db.execute(queryDelete)
logging.info('Deleted {} rows into table {}'.format(rows_before, table_name))
except:
logging.info('Deleted error into table {}'.format(table_name))
else:
pass
It seems when I run db.execute(queryDelete), it goes to the exception.
I have no message of error. But the query with count data is working...
thanks
I think that the reason for the error is because there are foreign keys against the table. In order to be sure, assign the exception into a variable and print it:
except Exception as ex:
print(ex)
By the way, if you want to quickly delete all of the rows from a table then
It will be much more efficient to truncate the table instead of deleting all the rows:
truncate table table_name
Delete is more useful when you want to delete rows under some conditions:
delete from table_name where ...
I am trying to get the ID of a newly inserted row by using OUTPUT. However, I encountered the HY010 error. The following query/code is what I use:
string = """
SET NOCOUNT ON;
DECLARE #NEWID TABLE(ID INT);
INSERT INTO dbo.t1 (Username, Age)
OUTPUT inserted.id INTO #NEWID(ID)
VALUES(?, ?)
SELECT ID FROM #NEWID
"""
cursor.execute(string, "John Doe", 35)
cursor.commit()
id = cursor.fetchone()[0]
the last line id = cursor.fetchone()[0] led to a HY010 error (see below). Any advice would be greatly appreciated!
pyodbc.Error: ('HY010', '[HY010] [Microsoft][ODBC SQL Server Driver]Function sequence error (0) (SQLFetch)')
I was able to reproduce your issue, and I was able to avoid it by retrieving the id value immediately after the INSERT and before the commit. That is, instead of
cursor.execute(string, "John Doe", 35)
cursor.commit()
id = cursor.fetchone()[0]
I did
cursor.execute(string, "John Doe", 35)
id = cursor.fetchone()[0] # although cursor.fetchval() would be preferred
cursor.commit()
For me only this worked with Azure SQL Serverless (using pyodbc==4.0.28):
cursor.execute(insert_statement, param_value_list)
cursor.execute("SELECT ##IDENTITY AS ID;")
return cursor.fetchone()[0]
If you're using SQLAlchemy with an engine, then you can retrieve the PyODBC cursor like this before running the query and fetching the table ID.
connection = sql_alchemy_engine.raw_connection()
cursor = connection.cursor()
result = cursor.execute(
"""
INSERT INTO MySchema.MyTable (Col1, Col2) OUTPUT INSERTED.MyTableId
VALUES (?, ?);
""",
col1_value,
col2_value,
)
myTableId = cursor.fetchone()[0]
cursor.commit()
print("my ID is:", myTableId)
I am trying to query the records for a specific ID in an Oracle table based on what the user inputs.
Here is my code:
import cx_Oracle
con = cx_Oracle.connect('dbuser/dbpassword#oracle_host/service_ID')
cur = con.cursor()
id_number = raw_input('What is the ID Number?')
cur.execute('select id, info from oracle_table_name where id=:id_number')
for result in cur:
print "test", result
cur.close()
con.close()
The following error pops up: cx_Oracle.DatabaseError: ORA-01008: not all variables bound
When I remove the user input and the variable substitution and run the query, everything works fine.
:id_number in your SQL is a parameter (variable). You need to provide its value.
execute method accepts parameters as the second argument.
Example:
query = "select * from some_table where col=:my_param"
cursor.execute(query, {'my_param': 5})
Check the documentation at http://cx-oracle.readthedocs.org/en/latest/cursor.html#Cursor.execute
I assigned a name to the user_value:
user_value = raw_input('What is the ID Number?')
And then referenced it in the execute statement:
cur.execute(query, {'id': (user_value)})
Thanks to Radoslaw-Roszkowiak for the assist!!
I have a MySQL Table named TBLTEST with two columns ID and qSQL. Each qSQL has SQL queries in it.
I have another table FACTRESTTBL.
There are 10 rows in the table TBLTEST.
For example, On TBLTEST lets take id =4 and qSQL ="select id, city, state from ABC".
How can I insert into the FACTRESTTBL from TBLTEST using python, may be using dictionary?
Thx!
You can use MySQLdb for Python.
Sample code (you'll need to debug it as I have no way of running it here):
#!/usr/bin/python
import MySQLdb
# Open database connection
db = MySQLdb.connect("localhost","testuser","test123","TESTDB" )
# prepare a cursor object using cursor() method
cursor = db.cursor()
# Select qSQL with id=4.
cursor.execute("SELECT qSQL FROM TBLTEST WHERE id = 4")
# Fetch a single row using fetchone() method.
results = cursor.fetchone()
qSQL = results[0]
cursor.execute(qSQL)
# Fetch all the rows in a list of lists.
qSQLresults = cursor.fetchall()
for row in qSQLresults:
id = row[0]
city = row[1]
#SQL query to INSERT a record into the table FACTRESTTBL.
cursor.execute('''INSERT into FACTRESTTBL (id, city)
values (%s, %s)''',
(id, city))
# Commit your changes in the database
db.commit()
# disconnect from server
db.close()