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Python SQL Server database loop not working

Using Python looping through a number of SQL Server databases creating tables using select into, but when I run the script nothing happens i.e. no error messages and the tables have not been created. Below is an extract example of what I am doing. Can anyone advise?
df = [] # dataframe of database names as example
for i, x in df.iterrows():
SQL = """
Drop table if exists {x}..table
Select
Name
Into
{y}..table
From
MainDatabase..Details
""".format(x=x['Database'],y=x['Database'])
cursor.execute(SQL)
conn.commit()

Looks like your DB driver doesn't support multiple statements behavior, try to split your query to 2 single statements one with drop and other with select:
for i, x in df.iterrows():
drop_sql = """
Drop table if exists {x}..table
""".format(x=x['Database'])
select_sql = """
Select
Name
Into
{y}..table
From
MainDatabase..Details
""".format(x=x['Database'], y=x['Database'])
cursor.execute(drop_sql)
cursor.execute(select_sql)
cursor.commit()
And second tip, your x=x['Database'] and y=x['Database'] are the same, is this correct?

Sqlite3 Python: can't use "limit" as column name

There are 6 columns and for some reason when my program gets to this bit of code during install, it simply creates a blank file with no table.
Through trial and error, I found the only thing that did not create a blank file was removing the limit row.
I have other code that runs and looks the same just for different databases and it works fine.
try:
# Connect to Database
conn = sqlite3.connect('databases/Categories.db')
cur = conn.cursor()
# Create Table
cur.execute("""CREATE TABLE categories (
priority text,
name text,
type text,
increment text,
total real,
limit real)""")
# Commit and Close
conn.commit()
conn.close()
except sqlite3.OperationalError:
pass

"limit" is an SQL keyword, for example, as in
SELECT foo
FROM bar
LIMIT 10;
If you want to use "limit" as a column name in sqlite, it needs to be quoted, in one of these ways:
'limit'
"limit"
[limit]
`limit`
So for example, your statement could be
cur.execute("""CREATE TABLE categories (
priority text,
name text,
type text,
increment text,
total real,
"limit" real)""")
Note that it must be quoted in other statements too, for example
"""INSERT INTO categories ("limit") VALUES (?);"""

I did some more testing and I fixed it by renaming the limit row to something else. Turns out, sqlite3 doesn't like rows named limit.

PostgreSQL query gives unexpected result

I'm trying to do something extremely simple that works, but not the way I expect it to. I have a database with various tables and for each of those tables, I'm trying to extract the column names from the information schema. I'm using the code below and everything works like a charm (python):
import psycopg2 as pgsql
# code to connect and generate cursor
table = 'some_table_name'
query = 'SELECT column_name FROM information_schema.columns WHERE table_name = %s'
cursor.execute(query, (table,))
result = pd.DataFrame(cursor.fetchall())
print(result)
So far, so good. The problem arises when I replace the query variable with the following:
import psycopg2 as pgsql
# code to connect and generate cursor
table = 'some_table_name'
**query = 'SELECT column_name FROM information_schema.columns WHERE table_name='+table
cursor.execute(query)**
result = pd.DataFrame(cursor.fetchall())
print(result)
If I print the statement, it's correct:
SELECT column_name FROM information_schema.columns WHERE table_name=some_table_name
However, when I run the query, I'm getting this error message:
UndefinedColumn: column "some_table_name" does not exist
LINE 1: ... FROM information_schema.columns WHERE table_name=some_tabl...
some_table_name is a table name as a parameter to the WHERE clause, not a column name. How is this even possible?
Thanks!

Your problem is that you haven't put some_table_name in quotes so it is treated as a column name, not a string literal. Why not stick with the first method which both worked and is in line with the psycopg documentation?

How can I insert data in a SQL-database with python and variable tablename, rows and values? [duplicate]

Question: Is it possible to use a variable as your table name without having to use string constructors to do so?
Info:
I'm working on a project right now that catalogs data from a star simulation of mine. To do so I'm loading all the data into a sqlite database. It's working pretty well, but I've decided to add a lot more flexibility, efficiency, and usability to my db. I plan on later adding planetoids to the simulation, and wanted to have a table for each star. This way I wouldn't have to query a table of 20m some planetoids for the 1-4k in each solar system.
I've been told using string constructors is bad because it leaves me vulnerable to a SQL injection attack. While that isn't a big deal here as I'm the only person with access to these dbs, I would like to follow best practices. And also this way if I do a project with a similar situation where it is open to the public, I know what to do.
Currently I'm doing this:
cursor.execute("CREATE TABLE StarFrame"+self.name+" (etc etc)")
This works, but I would like to do something more like:
cursor.execute("CREATE TABLE StarFrame(?) (etc etc)",self.name)
though I understand that this would probably be impossible. though I would settle for something like
cursor.execute("CREATE TABLE (?) (etc etc)",self.name)
If this is not at all possible, I'll accept that answer, but if anyone knows a way to do this, do tell. :)
I'm coding in python.

Unfortunately, tables can't be the target of parameter substitution (I didn't find any definitive source, but I have seen it on a few web forums).
If you are worried about injection (you probably should be), you can write a function that cleans the string before passing it. Since you are looking for just a table name, you should be safe just accepting alphanumerics, stripping out all punctuation, such as )(][;, and whitespace. Basically, just keep A-Z a-z 0-9.
def scrub(table_name):
return ''.join( chr for chr in table_name if chr.isalnum() )
scrub('); drop tables --') # returns 'droptables'

For people searching for a way to make the table as a variable, I got this from another reply to same question here:
It said the following and it works. It's all quoted from mhawke:
You can't use parameter substitution for the table name. You need to add the table name to the query string yourself. Something like this:
query = 'SELECT * FROM {}'.format(table)
c.execute(query)
One thing to be mindful of is the source of the value for the table name. If that comes from an untrusted source, e.g. a user, then you need to validate the table name to avoid potential SQL injection attacks. One way might be to construct a parameterised query that looks up the table name from the DB catalogue:
import sqlite3
def exists_table(db, name):
query = "SELECT 1 FROM sqlite_master WHERE type='table' and name = ?"
return db.execute(query, (name,)).fetchone() is not None

I wouldn't separate the data into more than one table. If you create an index on the star column, you won't have any problem efficiently accessing the data.

Try with string formatting:
sql_cmd = '''CREATE TABLE {}(id, column1, column2, column2)'''.format(
'table_name')
db.execute(sql_cmd)
Replace 'table_name' with your desire.

To avoid hard-coding table names, I've used:
table = "sometable"
c = conn.cursor()
c.execute('''CREATE TABLE IF NOT EXISTS {} (
importantdate DATE,
somename VARCHAR,
)'''.format(table))
c.execute('''INSERT INTO {} VALUES (?, ?)'''.format(table),
(datetime.strftime(datetime.today(), "%Y-%m-%d"),
myname))

As has been said in the other answers, "tables can't be the target of parameter substitution" but if you find yourself in a bind where you have no option, here is a method of testing if the table name supplied is valid.
Note: I have made the table name a real pig in an attempt to cover all of the bases.
import sys
import sqlite3
def delim(s):
delims="\"'`"
use_delim = []
for d in delims:
if d not in s:
use_delim.append(d)
return use_delim
db_name = "some.db"
db = sqlite3.connect(db_name)
mycursor = db.cursor()
table = 'so""m ][ `etable'
delimiters = delim(table)
if len(delimiters) < 1:
print "The name of the database will not allow this!"
sys.exit()
use_delimiter = delimiters[0]
print "Using delimiter ", use_delimiter
mycursor.execute('SELECT name FROM sqlite_master where (name = ?)', [table])
row = mycursor.fetchall()
valid_table = False
if row:
print (table,"table name verified")
valid_table = True
else:
print (table,"Table name not in database", db_name)
if valid_table:
try:
mycursor.execute('insert into ' +use_delimiter+ table +use_delimiter+ ' (my_data,my_column_name) values (?,?) ',(1,"Name"));
db.commit()
except Exception as e:
print "Error:", str(e)
try:
mycursor.execute('UPDATE ' +use_delimiter+ table +use_delimiter+ ' set my_column_name = ? where my_data = ?', ["ReNamed",1])
db.commit()
except Exception as e:
print "Error:", str(e)
db.close()

you can use something like this
conn = sqlite3.connect()
createTable = '''CREATE TABLE %s (# );''' %dateNow)
conn.execute(createTable)
basically, if we want to separate the data into several tables according to the date right now, for example, you want to monitor a system based on the date.
createTable = '''CREATE TABLE %s (# );''' %dateNow) means that you create a table with variable dateNow which according to your coding language, you can define dateNow as a variable to retrieve the current date from your coding language.

You can save your query in a .sql or txt file and use the open().replace() method to use variables in any part of your query. Long time reader but first time poster so I apologize if anything is off here.
```SQL in yoursql.sql```
Sel *
From yourdbschema.tablenm
```SQL to run```
tablenm = 'yourtablename'
cur = connect.cursor()
query = cur.execute(open(file = yoursql.sql).read().replace('tablenm',tablenm))

You can pass a string as the SQL command:
import sqlite3
conn = sqlite3.connect('db.db')
c = conn.cursor()
tablename, field_data = 'some_table','some_data'
query = 'SELECT * FROM '+tablename+' WHERE column1=\"'+field_data+"\""
c.execute(query)

Syntax error sqlite python [duplicate]

Question: Is it possible to use a variable as your table name without having to use string constructors to do so?
Info:
I'm working on a project right now that catalogs data from a star simulation of mine. To do so I'm loading all the data into a sqlite database. It's working pretty well, but I've decided to add a lot more flexibility, efficiency, and usability to my db. I plan on later adding planetoids to the simulation, and wanted to have a table for each star. This way I wouldn't have to query a table of 20m some planetoids for the 1-4k in each solar system.
I've been told using string constructors is bad because it leaves me vulnerable to a SQL injection attack. While that isn't a big deal here as I'm the only person with access to these dbs, I would like to follow best practices. And also this way if I do a project with a similar situation where it is open to the public, I know what to do.
Currently I'm doing this:
cursor.execute("CREATE TABLE StarFrame"+self.name+" (etc etc)")
This works, but I would like to do something more like:
cursor.execute("CREATE TABLE StarFrame(?) (etc etc)",self.name)
though I understand that this would probably be impossible. though I would settle for something like
cursor.execute("CREATE TABLE (?) (etc etc)",self.name)
If this is not at all possible, I'll accept that answer, but if anyone knows a way to do this, do tell. :)
I'm coding in python.

Unfortunately, tables can't be the target of parameter substitution (I didn't find any definitive source, but I have seen it on a few web forums).
If you are worried about injection (you probably should be), you can write a function that cleans the string before passing it. Since you are looking for just a table name, you should be safe just accepting alphanumerics, stripping out all punctuation, such as )(][;, and whitespace. Basically, just keep A-Z a-z 0-9.
def scrub(table_name):
return ''.join( chr for chr in table_name if chr.isalnum() )
scrub('); drop tables --') # returns 'droptables'

For people searching for a way to make the table as a variable, I got this from another reply to same question here:
It said the following and it works. It's all quoted from mhawke:
You can't use parameter substitution for the table name. You need to add the table name to the query string yourself. Something like this:
query = 'SELECT * FROM {}'.format(table)
c.execute(query)
One thing to be mindful of is the source of the value for the table name. If that comes from an untrusted source, e.g. a user, then you need to validate the table name to avoid potential SQL injection attacks. One way might be to construct a parameterised query that looks up the table name from the DB catalogue:
import sqlite3
def exists_table(db, name):
query = "SELECT 1 FROM sqlite_master WHERE type='table' and name = ?"
return db.execute(query, (name,)).fetchone() is not None

I wouldn't separate the data into more than one table. If you create an index on the star column, you won't have any problem efficiently accessing the data.

Try with string formatting:
sql_cmd = '''CREATE TABLE {}(id, column1, column2, column2)'''.format(
'table_name')
db.execute(sql_cmd)
Replace 'table_name' with your desire.

To avoid hard-coding table names, I've used:
table = "sometable"
c = conn.cursor()
c.execute('''CREATE TABLE IF NOT EXISTS {} (
importantdate DATE,
somename VARCHAR,
)'''.format(table))
c.execute('''INSERT INTO {} VALUES (?, ?)'''.format(table),
(datetime.strftime(datetime.today(), "%Y-%m-%d"),
myname))

As has been said in the other answers, "tables can't be the target of parameter substitution" but if you find yourself in a bind where you have no option, here is a method of testing if the table name supplied is valid.
Note: I have made the table name a real pig in an attempt to cover all of the bases.
import sys
import sqlite3
def delim(s):
delims="\"'`"
use_delim = []
for d in delims:
if d not in s:
use_delim.append(d)
return use_delim
db_name = "some.db"
db = sqlite3.connect(db_name)
mycursor = db.cursor()
table = 'so""m ][ `etable'
delimiters = delim(table)
if len(delimiters) < 1:
print "The name of the database will not allow this!"
sys.exit()
use_delimiter = delimiters[0]
print "Using delimiter ", use_delimiter
mycursor.execute('SELECT name FROM sqlite_master where (name = ?)', [table])
row = mycursor.fetchall()
valid_table = False
if row:
print (table,"table name verified")
valid_table = True
else:
print (table,"Table name not in database", db_name)
if valid_table:
try:
mycursor.execute('insert into ' +use_delimiter+ table +use_delimiter+ ' (my_data,my_column_name) values (?,?) ',(1,"Name"));
db.commit()
except Exception as e:
print "Error:", str(e)
try:
mycursor.execute('UPDATE ' +use_delimiter+ table +use_delimiter+ ' set my_column_name = ? where my_data = ?', ["ReNamed",1])
db.commit()
except Exception as e:
print "Error:", str(e)
db.close()

you can use something like this
conn = sqlite3.connect()
createTable = '''CREATE TABLE %s (# );''' %dateNow)
conn.execute(createTable)
basically, if we want to separate the data into several tables according to the date right now, for example, you want to monitor a system based on the date.
createTable = '''CREATE TABLE %s (# );''' %dateNow) means that you create a table with variable dateNow which according to your coding language, you can define dateNow as a variable to retrieve the current date from your coding language.

You can save your query in a .sql or txt file and use the open().replace() method to use variables in any part of your query. Long time reader but first time poster so I apologize if anything is off here.
```SQL in yoursql.sql```
Sel *
From yourdbschema.tablenm
```SQL to run```
tablenm = 'yourtablename'
cur = connect.cursor()
query = cur.execute(open(file = yoursql.sql).read().replace('tablenm',tablenm))

You can pass a string as the SQL command:
import sqlite3
conn = sqlite3.connect('db.db')
c = conn.cursor()
tablename, field_data = 'some_table','some_data'
query = 'SELECT * FROM '+tablename+' WHERE column1=\"'+field_data+"\""
c.execute(query)