I want to dump oracle objects like tables and stored procedures using cx_Oracle from python ,
is any tutorial how to do this ?
If you are looking for the source code for tables you can use the following:
select DBMS_METADATA.GET_DDL('TABLE','<table_name>') from DUAL;
for stored procedures you can use
select text from all_source where name = '<procedure name>'
In general this is not a cx_Oracle specific problem, just call the oracle specific tables (like all_source) or functions (like get_ddl) and read it in like any other query. There are more of these sorts of tables (like user_source for source that you the specific user own) in Oracle, but I'm doing this off the top of my head and don't have easy access to an Oracle db to remind myself.
Related
I'm not sure how to go about doing a one time load of the existing data I have in Oracle to MariaDB. I have DBeaver which I am using to access the databases. I saw an option in DBeaver to migrate the data from Source (Oracle) to Target (MariaDB) with a few clicks, but I'm not sure if that's the best approach.
Is writing a python script a better way of doing it? Should I download another tool to do a one time load? We are using CData Sync to do the incremental loads. Basically, it copies data from one database to another (Oracle to SQL Server for example) and it does incremental loads. I'm not sure if I can use it to do a full time/one time load of all the data I have in my Oracle database to MariaDB. I'm new to this, I've never loaded data before. The thing is, I have over 1100 tables so I can't manually write the schema for each table and do a "CREATE TABLE" statement for all 1100 tables...
Option 1 DBeaver
If DBeaver is willing to try it in a few clicks I'd try and see what it gives for some small tables.
Option 2 MariaDB connect
Alternately there MariaDB connect engine using ODBC or JDBC.
Note you don't need to create table structure for all, but do need the list of table and generate CREATE TABLE t1 ENGINE=CONNECT TABLE_TYPE=ODBC tabname='T1' CONNECTION='DSN=XE;.. for each table.
Then it would be:
create database mariadb_migration;
create table mariadb_migration.t1 like t1;
insert into mariadb_migration.t1 select * from t1;
Option 3 MariaDB Oracle Mode
This uses the Oracle compatibility mode of MariaDB.
Take a SQL dump from Oracle.
Prepend SET SQL_MODE='ORACLE'; to start of the dump.
Import this to MariaDB.
Option 4 SQLines
SQLines offer a Oracle to MariaDB
Small disclaimer, I've not done any of these personally, I just know these options exist.
How to convert a existing postgresql db into a Microsoft Access db with python?
I want to convert my postgresql db into a Microsoft Access db.
There are many possible solutions, like transfer table by table and inside the tables row by row.
But which of the solution mide be the best in terms of performance?
Install the ODBC driver and link the tables from PostgreSQL
Mark the link tables and choose Convert to local table
(Optional) Go to Database Tools, Access Database, and select to split the database to have the tables in an external Access database
I have 5 tables in an Oracle database. I need to create similar structures of them in AWS Redshift. I am using cx_oracle to connect to Oracle and dump the ddl in a csv file. But changing that DDL for each datatype in python to make it run in Redshift is turning out to be a very tedious process.
Is there any easy way to do in Python? Is there any library or function to do this seamlessly.
PS: I tried to use AWS Schema Conversion Tool for this. The tables got created in Redshift, but, with a glitch. Every datatype got doubled in Redshift.
For example: varchar(100) in Oracle became varchar(200) in Redshift
Has anyone faced a similar issue before with SCT?
The cx_OracleTools project and specifically the DescribeObject tool within that project have the ability to extract the DDL from an Oracle database. You may be able to use that.
I'm writing an application in Python and I'm using the Adodbapi package to handle my sql queries. For one part of the code, I need to communicate with an Access '97 (no, it's not a typo) database, and I want to get a list of the table names via an SQL statement. I've tried a bunch of statements using MSysObjects but I run into permissions isssues - no I don't have the option of opening the db in access and changing the permissions. I would imagine that Adodbapi has a way of accessing Schema information but I can't manage to find it.
Thanks in advance for your help.
I'm using python and psycopg2 to remotely query some psql databases, and I'm trying to figure out the best way to select the data I need from the remote table, and insert it into a table on a separate DB (local application server).
Most of the stuff I've read has directed me to avoid executemany and look toward COPY operations, but I'm unsure how to implement this on a specific select statement as opposed to the entire table. Should I be headed this way or am I completely off?
but I'm unsure how to implement this on a specific select statement as opposed to the entire table
COPY isn't limited to tables, you can use a query as the source as well, check out the examples in the manual, it shows how to use COPY to create a text file based on a query:
http://www.postgresql.org/docs/current/static/sql-copy.html#AEN59055
(3rd example)
Take a look at http://ryrobes.com/featured-articles/using-a-simple-python-script-for-end-to-end-data-transformation-and-etl-part-1/
Granted, this is pulling from Oracle and inserting into SQL Server, but the concepts should be the same.