Oracle to Mysql (dates) Help please

[duikboot]

Hi all,

I'm trying to export a view tables from a Oracle database to a Mysql
database. I create insert statements (they look alright), but it all goes
wrong when I try to execute them in Mysql, because the dates must have
quotes on each side.
I just don't know how make the dates right.
Well I'll just show you the code and some insert statements it generates.
Could anyone please help me?

Thanks,

Arjen

####Code####

import cx_Oracle
tabellen=["machine"]
con_oracle=cx_Oracle.connect("bla/bla")
c_oracle=con_oracle.cursor()

import MySQLdb
my=MySQLdb.Connect("localhost", db="bla")
my_mysql=my.cursor()
for tabel in tabellen:
print tabel
c_oracle.execute("select * from %s" % tabel)
a_oracle=c_oracle.fetchone()
#file=open("%s.sql" % tabel, 'w')
while a_oracle != None:
b=str(a_oracle)
ins="insert into %s values %s;\n" % (tabel, b)
#file.write(ins)
my_mysql.execute(ins)
#print ins

a_oracle=c_oracle.fetchone()
file.close()

con_oracle.close()

my.close()


##insert statement###

insert into machine values ('230KM', ' ', '230KM', 1980-01-01 00:00:00,
2035-01-01 00:00:00, 1, 100, 'asap', 'NO', 0, 0, 'corrugator', 2003-12-04
06:00:00, 1970-01-01 01:00:00, ' ', 'normal', 0.0, 0.0, 7, ' ', ' ',
'normal', ' ', ' ', 'A', 2003-12-04 09:42:14, 82766);

 

[Dennis Lee Bieber]

duikboot fed this fish to the penguins on Sunday 11 January 2004 05:31
am:

ins="insert into %s values %s;\n" % (tabel, b)
#file.write(ins)
my_mysql.execute(ins)
#print ins

Don't do that.

It appears you are trying to build a string with multiple insert
statements for a single execute call.

If you accept the overhead of single inserts, the execute can do the
parsing and theoretically will properly quote needed fields...

my_mysql.execute("insert into %s values %s", (tabel, b))


If you really want a single execute, look at the specs for executemany
(you'll need to build a tuple of tuples: ( (tabel1, b1), (tabel2, b2),
...., (tabelN, Bn) ) but the rest looks similar)

--

 

[Dennis Lee Bieber]

Dennis Lee Bieber fed this fish to the penguins on Sunday 11 January
2004 11:02 am:

(you'll need to build a tuple of tuples: ( (tabel1, b1), (tabel2, b2),
..., (tabelN, Bn) ) but the rest looks similar)

Whoops, slight mistake there -- I hadn't quite noticed that the first
term was the relation itself, and each Bx contained all the values for
one row.

Someone else has the more correct variation...

--

 

[duikboot]

Could you please explain that?

Cheers,

Arjen

Dennis Lee Bieber fed this fish to the penguins on Sunday 11 January
2004 11:02 am:


Whoops, slight mistake there -- I hadn't quite noticed that the first
term was the relation itself, and each Bx contained all the values for
one row.

Someone else has the more correct variation...

 

[Dennis Lee Bieber]

duikboot fed this fish to the penguins on Tuesday 13 January 2004 01:13
am:

Could you please explain that?

See the reply <[email protected]>
(Pieter Claerhout) -- though according to my documents, the method is
executemany(), not execute_many().


--

 

[duikboot]

Sorry, I can't find it. Can you quote it for me, please?

 

[Dennis Lee Bieber]

duikboot fed this fish to the penguins on Wednesday 14 January 2004
01:07 am:

Sorry, I can't find it. Can you quote it for me, please?

Hopefully without offending anyone... Formatting may be a bit off,
since I'm including the basic headers for completeness...

RE: Oracle to Mysql (dates) Help please

From:

Pieter Claerhout <[email protected]>

Date:

Sunday 11 January 2004 07:25:09 am

To:

duikboot <[email protected]>, (e-mail address removed)

Groups:

comp.lang.python



no references





What your seeing in the insert statement is not a string, but is a DateTime
object, which needs to be converted to the correct representation for the
target database.

Prepared statements are the best option here. With prepared statements, the
data conversion happens automagically.

The code will then look as follows:

## BEGIN CODE
import cx_Oracle
import MySQLdb

tabellen = [ 'machine' ]

connO = cx_Oracle.connect( 'bla/bla' )
cursO = connO.cursor()
connM = MySQLdb.Connect( 'localhost', db='bla' )
cursM = connM.cursor()

for tabel in tabellen:
print tabel
cursO.execute( 'select * from ' + tabel )
results = cursO.fetchall()
cursM.execute_many(
'insert into ' + tabel + ' values ( %s,%s,%s,%s,%s )',
results
)
# END CODE

A few notes:
- This uses the execute_many function which will speed up the insert process
quite a lot.
- Instead of fetching one record at a time, all records are fetched at once.
- The number of "%s" in the insert statement will depend on the number of
columns in the target table. You could look at the first row of the results
variable to know how many columns there are in the table.
- The type of placeholders in the SQL statement depend on the database.

More info on execute_many and other can be found on:
http://www.python.org/peps/pep-0249.html (look for paramstyle and
execute_many).

Cheers,


pieter

Creo
pieter claerhout | product support prinergy | tel: +32 2 352 2511 |
(e-mail address removed) | www.creo.com

IMAGINE CREATE BELIEVE(tm)


-----Original Message-----
From: duikboot [mailto:[email protected]]
Sent: 11 January 2004 14:32
To: (e-mail address removed)
Subject: Oracle to Mysql (dates) Help please


Hi all,

I'm trying to export a view tables from a Oracle database to a Mysql
database. I create insert statements (they look alright), but it all goes
wrong when I try to execute them in Mysql, because the dates must have
quotes on each side.
I just don't know how make the dates right.
Well I'll just show you the code and some insert statements it generates.
Could anyone please help me?

Thanks,

Arjen

####Code####

import cx_Oracle
tabellen=["machine"]
con_oracle=cx_Oracle.connect("bla/bla")
c_oracle=con_oracle.cursor()

import MySQLdb
my=MySQLdb.Connect("localhost", db="bla")
my_mysql=my.cursor()
for tabel in tabellen:
print tabel
c_oracle.execute("select * from %s" % tabel)
a_oracle=c_oracle.fetchone()
#file=open("%s.sql" % tabel, 'w')
while a_oracle != None:
b=str(a_oracle)
ins="insert into %s values %s;\n" % (tabel, b)
#file.write(ins)
my_mysql.execute(ins)
#print ins

a_oracle=c_oracle.fetchone()
file.close()

con_oracle.close()

my.close()


##insert statement###

insert into machine values ('230KM', ' ', '230KM', 1980-01-01 00:00:00,
2035-01-01 00:00:00, 1, 100, 'asap', 'NO', 0, 0, 'corrugator', 2003-12-04
06:00:00, 1970-01-01 01:00:00, ' ', 'normal', 0.0, 0.0, 7, ' ', ' ',
'normal', ' ', ' ', 'A', 2003-12-04 09:42:14, 82766);



http://mail.python.org/mailman/listinfo/python-list

--

 

[duikboot]

Thank you all very much for your help.

I'll think it will work now (don't know yet, I'll work on it later this
week)


Cheers Arjen
(If you're interested, I will post the solution that worked for me)