I am trying to migrate data from table A of database DB1 to table B of database DB2 using java and Oracle.
I am using java 1.8 and my source database has Oracle 11g and destination database has Oracle 12c.
I made structure (scema, tables )of destination database in source database. And migrating as by making use of *insert into dest select * from source* query in java . but as the number of records in source table in millions so it's consuming time.. and later on this migrated data i want to export into my actual destination so that too will going to take time.
As per my little knowledge.. i think I can't use prepared statement with 2 connection. Because my table consists of 400 to 500 columns , so binding that many columns with prepared statement is not a good idea. Also my structure of source and destination tables are different. I made the field mapping in properties file where I mapped the old field to new field for insert into select * from tbl query. Like my source table has column as col0001 and the corresponding column in destination is ref_no. So this too will not allow me to use prepared statement. But by making use of statement in java i can migrate data in single dB only.
I tried with dblink also. But for clob datatype i am not able to migrate data.
Kindly provide the solution if anyone did something like this previously.
For a one-off copy, you can do a direct mode insert:
insert /*+ APPEND */ into local_table select * from table#database_link;
Here are some other related links.
Related
I have a remote database that I want to copy on my local SQL Server.
IMPORTANT: I only want a sample data (1k rows for instance) from each table, and there are about 130 different tables.
I have tried to use the export data procedure in SSMS. Put simply, I go to TASKS> EXPORT DATA > CHOSE SOURCE (the remote db)> CHOSE DESTINATION (my local db) > CHOSE THE TABLES TO COPY > COPY
What I have tried:
I've tried to write down in this tool the SQL query like
SELECT TOP 1000 *
FROM TABLE1 GO ...
SELECT TOP 1000 *
FROM TABLE130
But on the mapping step, it puts every result within a single table instead of creating the 130 different output tables.
FYI, the above procedure is taking 2min for one table. Doing it one by one for each table will take 130 *2min = 4hours and half... plus it is so boring
Do you have any idea for resolving this situation?
Thank you
regards
If you only want a subset you are going to have problems with foreign keys, if there are any in your database.
Possible approaches to extract all data or a subset
Use SSIS to extract the data from the source db and load into your local db
Write a custom application that does the job. (You can use SQL Bulk Copy)
If you purely wan't to do do it in SSMS you can create a linked server on your local server to the remote server.
This way you can do something like this if the tables or not yet created on your local server:
SELECT TOP 1000 *
INSERT INTO [dbo].Table1
FROM [yourLinkedServer].[dbo].[Table1]
Changing the INTO table and FROM table for each table you want to copy.
I cannot use linked server.
Both databases on both servers have the same structure but different data.
I have 10k rows to transfer from the DB on one server to the same DB on the other. I cannot restore the DB on the other server as it will take a huge amount of space that I don't have on the other server.
So, I have 2 options that I don't know how to execute:
Backup and restoring only one table - the table is linked to many other tables but these other tables exist on the other server too. Can I somehow delete or remove the other tables or make a backup only over one table?
I need to transfer 10k rows. How is it possible to create 10k insert queries based on selected 10k rows?
Can I somehow delete or remove the other tables or make a backup only over one table?
No you can not do this, unfortunately
How is it possible to create 10k insert queries based on selected 10k rows?
Right-click on Database -> Tasks -> Generate scripts -> (Introduction) Next
Chose Select specific database objects -> Tables, chose table you need -> Next
Advanced -> Search for Types of data script change from Schema only (by default) to Data only -> OK
Chose where to save -> Next -> Next. Wait the operation to end.
This will generate the file with 10k inserts.
Another way is to use Import/Export wizard (the most simple way for one-time-import/export) if you have link between databases.
There are many ways to choose from, here is one way using BCP. That's a tool that ships with SQL Server to Import and Export Bulk Data.
The outlines of the process:
Export the data from the source server to a file using BCP - BCP OUT for a whole table, or BCP QUERYOUT with a query to select the 10k rows you want exported
Copy the file to the destination server
Import the data using BCP on the destination database - BCP IN.
My suggestion would be to export these rows to excel( you can do this by copy pasting your query output) and transfer this to other server and import it there.
this is the official method :-
https://learn.microsoft.com/en-us/sql/relational-databases/import-export/import-data-from-excel-to-sql
and this is the the unofficial method :
http://therealdanvega.com/blog/2010/08/04/create-sql-insert-statements-from-a-spreadsheet.
Here I have assumed that you only need to transfer the transactional data and your reference data is same on both server. So you will need to execute only one query for exporting your data
I would definietely go down the SSIS route once you use SSIS to do a task like this you will not use anything else very simple to script up. You can use any version and it will be a simple job and very quick.
Open new SSIS project in available visual studio version/s there are many different but even a 2008 version will do this simple task you may have to install integration services or something similar used to be called bids (business information development studio in 2008) (anything up to 2015 although support is nearly there in 2017)
add a data flow task
double click the data flow task
Bottom of screen add two connection managers (1 to source and 1 to destination database)
add oledb source pointing to source database table
add oledb destination pointing to destination database table
drag line between the source and destination (should auto map all columns if the same name)
hit Start and the data will flow very quickly
you have create DbInstaller. using dbInstaller you have share whole database. Dbinstaller work both ado.Net and Entity Frame Work but I have using Entity Frame Work.
you can do it by sql server query
first select first database like
Use database1 --- this will be your first database
after select first database we will put our table row in temp table by this query
select * into #Temp from select * from table1
now we select second database and insert temp table data into second database table by this code
use secondDatabaseName
INSERT INTO tableNameintoinsert (col1, col2, )
SELECT col1, col2 FROM #temp;
I have a table with 103 columns and more than 100,000 records. I was told that Oracle Data base has bad data in few of the columns(four columns) and in few of the records(20,000 records approx) and was told to modify data. Also I was given a query where I should modify data(bad data). With the help of query, I exported all the bad data into excel and modified using macros.
How to replace existing bad data in Oracle data base to data which I have in excel(good data). Is it possible to modify data in some part of the database using SQL query? I mean to say 4 out of 103 columns and 20k out of 100k records has to be modified without affecting already existing good data in Oracle database.
I am using SQL developer and Oracle 11g
My query to retrieve bad data
select e.id_number
, e.gender_code
, e.pref_mail_name
, e.prefix
,e.first_name
,e.last_name
,e.spouse_name
,e.spouse_id_number
,e.pref_jnt_mail_name1
,e.pref_jnt_mail_name2
from advance.entity e
where e.person_or_org = 'P'
and ascii(e.spouse_name) <> 32
or ascii(e.spouse_id_number) <> 32"
Note: Moreover I am not changing any primary key or secondary key data. Bad data is in other columns.
You can start by importing all corrected data (which now resides in your Excel file), to a temporary table. See Load Excel data sheet to Oracle database for more details.
The it should be a simple task to write one or more UPDATE statements. If you are new to Oracle syntax, Tech on the Net has some nice examples.
Also, do not forget to backup the original table to a temporary table before you make any changes there. That way, if you mess up the data repair, you can start over.
I want to Copy a data from One oracle database to another.
I have checked Import/Export Utility but the problem is import utility doesn't support conflicts resolution techniques between rows.
For Example if there's a table in the source database have the same row key in the destination database. if i use 'Ignore' parameter with value = y, the destination table will have a duplicate rows.
I want to ask if there's another way to import data from oracle database to another with some mechanism of detecting the conflicts and resolve them?
You might want to consider using a database link from database A to database B. You can query the data from database B to insert into your database A tables. You are free to query whatever you want using SQL or PL/SQL.
More on database links:
http://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_5005.htm
I have to copy the tables with data from one database to another using Query. I know how to copy tables with data within a database. But I was not sure about how to do the same for copying between two databases.
I have to copy huge number of tables, so I need any fast method using query...
Anybody please help out...Thanks in advance...
You can use the same way to copy the tables within one database, the SELECT INTO but use a fully qualified tables names database.schema.object_name instead like so:
USE TheOtherDB;
SELECT *
INTO NewTable
FROM TheFirstDB.Schemaname.OldTable
This will create a new table Newtable in the database TheOtherDB from the table OldTable whih belongs to the databaseTheFirstDB
Right click on the database, select tasks and click on Generate Scripts.
In the resultant pop-up, choose options as required (click advanced), to drop and create table, drop if exists, etc.
Scroll down and choose "Schema and Data" or "Data Only" or "Types of data to script (2008 R2)"as required.
Save to file and execute on the destination DB.
Advantages -
Can be executed against the destination DB, even if it is on another server / instance
Quickly script multiple tables, with data as needed
Warning - Might take quite a while to script, if the tables contain a large amount of data.
Rajan
INSERT INTO DB2.dbo.MyOtherTable (Col0, Col1)
SELECT Col0, Col1 FROM DB1.dbo.MyTable
Both table column's must have same data types..
Below SQL Query will copy SQL Server table schema & data from one database to another database. You can always table name (SampleTable) in your destination database.
SELECT * INTO DestinationDB.dbo.SampleTable FROM SourceDB.dbo.SampleTable