I connected to my oracle database with cx_Oracle, had good connection and read needed data from base. Then tried to insert something in base and failed.
try:
print uid2 + "/" + pwd2 + "#" + service1
dconn1 = cx_Oracle.connect(uid2 + "/" + pwd2 + "#" + service1)
except:
pass
print dconn1
ver = dconn1.version.split(".")
print ver
cur = dconn1.cursor()
pdb.set_trace()
rows=[("NET-CI99999")]
sql_test='insert into Device2M1 (logical_name) values (:1)'
sql_test_2='insert into Device2M1 (logical_name) values ("NET-CI99999")'
#cur.prepare(sql_insert)
#cur.execute(sql_test_2)
cur.prepare(sql_test)
cur.executemany(None,rows)
dconn1.commit()
cur.execute("select logical_name,serial_no_,location,id,updated_by,contact_name,istatus,subtype,user_id,sysmodtime,sysmoduser,title,email,extension,ip_address,mac_address,updated_by, ig_fqdn,ig_domain,ig_model,ig_vendor,ig_inventory_numb,ig_network_equip,ig_name,ig_asset_tag,ig_it_asset_id,ig_it_asset_created,ig_registrator from Device2M1 where logical_name='NET-CI13681'")
for result in cur:
for i in result:
# pdb.set_trace()
print i
cur.close()
dconn1.close()
Part of the code with selections worked well, when try do just cur.execute for insertion console hang and make no replay, when try to do something with executemany have an error "cx_Oracle.DatabaseError: ORA-01036: неверное имя/номер переменной (wrong name/number of the variable)". Any idea about what is this and what could I do for proper working of the code?
Related
windows 7
python 2.7
Django 1.11
I have used Django to develop a website. In the backend I have the sqlite database which have 2 tables. One table accepts the form user submitted, and the other is for comparison.
Once a form A is submitted by the user, it will be save under table catalog_fw, and the catalog_fw.ODM and catalog_fw.project_name will be compared with the ones in the table catalog_fw_instance. If one line have the exact same content for catalog_fw.ODM and catalog_fw.project, catalog_fw_instance.level will be combined with A to pass to the an .exe to generate a txtx file.
However, error occurs in this line： c.execute("catalog_fw_instance.level,......
`
when I run this python file：
sqlite3.OperationalError: near "catalog_fw_instance": syntax error
The code to get sqlite data, compare and pass to the .exe is here:
def when_call_exe():
with sqlite3.connect('db.sqlite3') as con:
c = con.cursor()
#c.execute("catalog_fw_instance.level, SELECT catalog_fw.ODM_name, catalog_fw.project_name, catalog_fw.UAP, catalog_fw.NAP, catalog_fw.LAP, catalog_fw.num_address FROM catalog_fw INNER JOIN catalog_fw_instance ON catalog_fw.ODM_name=catalog_fw_instance.ODM_name AND catalog_fw.project_name=catalog_fw_instance.project_name")
sql = ("SELECT catalog_fw.ODM_name, catalog_fw.project_name, catalog_fw.UAP, catalog_fw.NAP, catalog_fw.LAP, " +
"catalog_fw.num_address, catalog_fw_instance.level " +
"FROM catalog_fw catalog_fw" +
"INNER JOIN catalog_fw_instance catalog_fw_instanc" +
" ON catalog_fw.ODM_name = catalog_fwi.ODM_name AND catalog_fw.project_name = catalog_fw_instance.project_name")
c.execute(sql)
print '1:', c.fetchone()
parameter = c.fetchone()
print '2', parameter
#pass to exe
args = ['.//exe//Test.exe', parameter[0], parameter[1]+parameter[2], parameter[3], parameter[4], parameter[5], parameter[6]]
output = my_check_output(args)
if 'SUCCESS' in output:
filename = output[28:-1]
else:
filename = output[8:-1]
downloadlink = os.path.join('/exe', '%s' % filename)
#save link to sqlite db
c.execute('''UPDATE catalog_fw SET download = %s WHERE
ODM_Name=parameter[1] AND project_Name=parameter[2] ''' % downloadlink)
here shows the 2 tables in the sqlite database
table 1
table 2
As far as I know, when calling cursor#execute() in Python, we should be passing a single string containing the query to be run. It looks like you are passing one of the select parameters, followed by a query, all together as a single string. Consider the following version:
c = con.cursor()
sql = ("SELECT cf.ODM_name, cf.project_name, cf.UAP, cf.NAP, cf.LAP, " +
"cf.num_address, cfi.level " +
"FROM catalog_fw cf " +
"INNER JOIN catalog_fw_instance cfi " +
" ON cf.ODM_name = cfi.ODM_name AND cf.project_name = cfi.project_name")
c.execute(sql)
print(c.fetchone())
parameter = c.fetchone()
When I run a query from sqlite browser the table get updated but when I use same query from Python the database won't get updated:
def updateDB (number, varCheck=True):
conn = sqlite3.connect(db)
c = conn.cursor()
i = 1
for each_test in number:
c.execute("UPDATE table1 SET val='%s' WHERE amount='%s' AND rank='%s'" % (each_test , str(i), 'rank2'))
i += 1
conn.commit()
conn.close()
return True
How can I fix the issue? I run python code as sudo.
In the past, I had similar issues while creating sql queries. I doubt if your sql query is being correctly formatted. The % string interpolation method can be a problem. Try using the .format() on the sql query string. PEP3101 explains the same about using .format() instead of % operator for string interpolation.
val='"' + each_test + '"'
amount = '"' + str(i) + '"'
rank= '"' + "rank2" + '"'
sql_qeury = "UPDATE table1 SET val={val} WHERE amount={amount} AND rank={rank}".format(val=val,amount=amount,rank=rank)
I have following code to execute sql quesry in Oracle db:
try:
conn = cx_Oracle.connect(DB_LOGIN+"/"+DB_PWD+"#"+SID)
cursor = connection.cursor()
cursor.execute(sql)
connection.commit()
cursor.close()
conn.close()
except cx_Oracle.DatabaseError, ex:
error, = ex.args
print 'Error.code =', error.code
print 'Error.message =' , error.message
print 'Error.offset =', error.offset
conn.rollback()
I got error: DatabaseError: <cx_Orac...40066758>.
Why I don't see full error message in console? Looks like exception part is not executed.
I use python 2.5 and oracle 10.2.0 on linux.
Update: After some investigation I found out that the error is DatabaseError: ORA-00911: invalid character.
My sql string is like: sql = "SELECT ID FROM TABLE WHERE DESC = '" + str(desc[0]) + "';". This is generated string: "SELECT ID FROM TABLE WHERE DESC = '3312';"
When I execute the same request in SQL Developer it works. So what I do wrong?
Delete the semicolon:
sql = "SELECT ID FROM TABLE WHERE DESC = '" + str(desc[0]) + "'"
I have this code:
dsn = cx_Oracle.makedsn(hostname, port, sid)
orcl = cx_Oracle.connect(username + '/' + password + '#' + dsn)
curs = orcl.cursor()
sql = "select TEMPLATE from my_table where id ='6'"
curs.execute(sql)
rows = curs.fetchall()
print rows
template = rows[0][0]
orcl.close()
print template.read()
When I do print rows, I get this:
[(<cx_Oracle.LOB object at 0x0000000001D49990>,)]
However, when I do print template.read(), I get this error:
cx_Oracle.DatabaseError: Invalid handle!
Do how do I get and read this data? Thanks.
I've found out that this happens in case when connection to Oracle is closed before the cx_Oracle.LOB.read() method is used.
orcl = cx_Oracle.connect(usrpass+'#'+dbase)
c = orcl.cursor()
c.execute(sq)
dane = c.fetchall()
orcl.close() # before reading LOB to str
wkt = dane[0][0].read()
And I get: DatabaseError: Invalid handle!
But the following code works:
orcl = cx_Oracle.connect(usrpass+'#'+dbase)
c = orcl.cursor()
c.execute(sq)
dane = c.fetchall()
wkt = dane[0][0].read()
orcl.close() # after reading LOB to str
Figured it out. I have to do something like this:
curs.execute(sql)
for row in curs:
print row[0].read()
You basically have to loop through the fetchall object
dsn = cx_Oracle.makedsn(hostname, port, sid)
orcl = cx_Oracle.connect(username + '/' + password + '#' + dsn)
curs = orcl.cursor()
sql = "select TEMPLATE from my_table where id ='6'"
curs.execute(sql)
rows = curs.fetchall()
for x in rows:
list_ = list(x)
print(list_)
There should be an extra comma in the for loop, see in below code, i have supplied an extra comma after x in for loop.
dsn = cx_Oracle.makedsn(hostname, port, sid)
orcl = cx_Oracle.connect(username + '/' + password + '#' + dsn)
curs = orcl.cursor()
sql = "select TEMPLATE from my_table where id ='6'"
curs.execute(sql)
rows = curs.fetchall()
for x, in rows:
print(x)
I had the same problem with in a slightly different context. I needed to query a +27000 rows table and it turns out that cx_Oracle cuts the connection to the DB after a while.
While a connection to the db is open, you can use the read() method of the cx_Oracle.Lob object to transform it into a string. But if the query brings a table that is too big, it won´t work because the connection will stop at some point and when you want to read the results from the query you´ll gt an error on the cx_Oracle objects.
I tried many things, like setting
connection.callTimeout = 0 (according to documentation, this means it would wait indefinetly), using fetchall() and then putting the results on a dataframe or numpy array but I could never read the cx_Oracle.Lob objects.
If I try to run the query using pandas.DataFrame.read_sql(query, connection) The dataframe would contain cx_Oracle.Lob objects with the connection closed, making them useless. (Again this only happens if the table is very big)
In the end I found a way of getting around this by querying and creating a csv file inmediatlely after, even though I know it´s not ideal.
def csv_from_sql(sql: str, path: str="dataframe.csv") -> bool:
try:
with cx_Oracle.connect(config.username, config.password, config.database, encoding=config.encoding) as connection:
connection.callTimeout = 0
data = pd.read_sql(sql, con=connection)
data.to_csv(path)
print("FILE CREATED")
except cx_Oracle.Error as error:
print(error)
return False
finally:
print("PROCESS ENDED\n")
return True
def make_query(sql: str, path: str="dataframe.csv") -> pd.DataFrame:
if csv_from_sql(sql, path):
dataframe = pd.read_csv("dataframe.csv")
return dataframe
return pd.DataFrame()
This took a long time (about 4 to 5 minutes) to bring my +27000-rows table, but it worked when everything else didn´t.
If anyone knows a better way, it would be helpful for me too.
I am trying to update an entry in a table usinig Python cx_oracle. The column is named "template" and it has a data type of CLOB.
This is my code:
dsn = cx_Oracle.makedsn(hostname, port, sid)
orcl = cx_Oracle.connect(username + '/' + password + '#' + dsn)
curs = orcl.cursor()
sql = "update mytable set template='" + template + "' where id='6';"
curs.execute(sql)
orcl.close()
When I do this, I get an error saying the string literal too long. The template variable contains about 26000 characters. How do I solve this?
Edit:
I found this: http://osdir.com/ml/python.db.cx-oracle/2005-04/msg00003.html
So I tried this:
curs.setinputsizes(value = cx_Oracle.CLOB)
sql = "update mytable set template='values(:value)' where id='6';"
curs.execute(sql, value = template)
and I get a "ORA-01036: illegal variable name/number error"
Edit2:
So this is my code now:
curs.setinputsizes(template = cx_Oracle.CLOB)
sql = "update mytable set template= :template where id='6';"
print sql, template
curs.execute(sql, template=template)
I get an ORA-00911: invalid character error now.
Inserting values in sql statements is a very bad practice. You should use parameters instead:
dsn = cx_Oracle.makedsn(hostname, port, sid)
orcl = cx_Oracle.connect(username + '/' + password + '#' + dsn)
curs = orcl.cursor()
curs.setinputsizes(template = cx_Oracle.CLOB)
sql = "update mytable set template= :template where id='6'"
curs.execute(sql, template=template)
orcl.close()
Use IronPython
import sys
sys.path.append(r"...\Oracle\odp.net.11g.64bit")
import clr
clr.AddReference("Oracle.DataAccess")
from Oracle.DataAccess.Client import OracleConnection, OracleCommand, OracleDataAdapter
connection = OracleConnection('userid=user;password=hello;datasource=database_1')
connection.Open()
command = OracleCommand()
command.Connection = connection
command.CommandText = "SQL goes here"
command.ExecuteNonQuery()
Change your table definition. A varchar2 field can store up to 32767 bytes; so, if you're using an 8-bit encoding, you have a bit of room left to play with before resorting to LOBs.