While development I was in need to create sqlite data base using dataset.
First create empty database file in sqlite. Then using dataset create table and dump data.
Is it possible using some dataset method?
I have done one thing
I have used one query
select * from sqlite_master where type='table'
That will give me schema of sqllite file from where I want to copy data.
On other end I will execute query return by above query.
That will help to create table dynamically.
On by one I used dataadapter to fill data and assigned dataset datatable data and used
Dataadapter. Update method.
Related
I'm currently trying to create txt files from all tables in the dbo schema
I have like 200s-300s tables there, so it would takes up too much times to create it manually..
I was thinking for creating a loop.
so as example (using AdventureWorks2019) :
select t.name as table_name
from sys.tables t
where schema_name(t.schema_id) = 'Person'
order by table_name;
This would get all the table name within the Person schema.
So I would loop :
Table input : select * from ${table_name}
But then i realized that for txt files, i need to declare all the field and their data types in pentaho, so it would become a problems.
Any ideas how to do this "backup" txt files?
Using Metadata Injection and more queries to the schema catalog tables in SQL Server. You not only need to retrieve the table name, you would need to afterwards retrieve the columns in that table and the data types, and inject that information (metadata) to the text output step.
You have in the samples directory of your spoon installation an example on how to use Metadata Injection, use it, along with the documentation, to build a simple example (the check to generate a transformation with the metadata you have injected is of great use to debug)
I have something similar to copy data from one database to another, both in Oracle, but with SQL Server you have similar catalog tables as in Oracle to retrieve the information you need. I created a simple, almost empty transformation to read one table and write to another. This transformation has almost no information, only the database origin in the Table Input step and the target database in the Table Output step:
And then I have a second transformation where I fill up all the information (metadata) to inject: The query to perform in the Table Input step, and all the data I need in the Table Output: Target table, if I need to truncate before inserting, the columns from (stream field) and to (Table field):
I need to do an Oracle data migration from 11g to 12c where schema changes are abundant. I have an excel sheet which describes all the schema changes. Excel sheet has the columns for 'old_table_name', 'old_column_name', 'old_value' and same for the new tables. Some values can be directly copied to the new table and some cannot be done that way.
For example I have to transform the old column value when it is moved to the new table. Some transformation are complex and they cannot be simply mapped. They should be transformed by joining with other tables in the old database. I was trying the Talend Open Studio Data Integration tool for this and found it is a bit complex to go ahead with that tool in my case. Does anyone have an idea of getting this done using Talend or any other tool? What is the ideal approach when doing a migration like this? I have included a sample of the excel sheet below which only has simple transformations.
The kind of converions shown in the spreadsheet can all be performed on the table itself using rename statements and/or basic ddl and dml statements. I would load the old table into the new database and perform these statement on the table.
alter table
old_table_one
rename to
new_table_one;
alter table
new_table_one
rename column
old_col_one
to
new_col_one;
update new_table_one
set new_col_one = 'A_NEW'
where new_col_one = 'A';
etc.
Based in the csv file column header it should create table dynamically and also insert records of that csv file into the newly create table.
Ex:
1) If i upload a file TEST.csv with 3 columns, it should create a table dynamically with three
2) Again if i upload a new file called TEST2.csv with 5 columns, it should create a table dynamically with five columns.
Every time it should create a table based on the uploaded csv file header..
how to achieve this in oracle APEX..
Thanks in Advance..
Without creating new tables you can treat the CSVs as tables using a TABLE function you can SELECT from. If you download the packages from the Alexandria Project you will find a function that will do just that inside CSV_UTIL_PKG (clob_to_csv is this function but you will find other goodies in here).
You would just upload the CSV and store in a CLOB column and then you can build reports on it using the CSV_UTIL_PKG code.
If you must create a new table for the upload you could still use this parser. Upload the file and then select just the first row (e.g. SELECT * FROM csv_util_pkg.clob_to_csv(your_clob) WHERE ROWNUM = 1). You could insert this row into an Apex Collection using APEX_COLLECTION.CREATE_COLLECTION_FROM_QUERY to make it easy to then iterate over each column.
You would need to determine the datatype for each column but could just use VARCHAR2 for everything.
But if you are just using generic columns you could just as easily just store one addition column as a name of this collection of records and store all of the uploads in the same table. Just build another table to store the column names.
Simply store this file as BLOB if structure is "dynamic".
You can use XML data type for this use case too but it won't be very different from BLOB column.
There is a SecureFile feature since 11g, It is a new BLOB implementation, it performs better than regular BLOB and it is good for unstructured or semi structured data.
I want to create a table (lets say table_copy) which has same columns as other table (lets call it table_original) in Oracle database, so the query will be like this :
create table table_copy as (select * from table_original where 1=0);
This will create a table, but the constraints of table_original are not copied to table_copy, so what should be done in this case?
Only NOT NULL constraints are copied using Create Table As Syntax (CTAS). Others should be created manually.
You might however query data dictionary view to see the definitions of constraints and implement them on your new table using PL/SQL.
The other tool that might be helpful is Oracle Data Pump. You could import the table using REMAP_TABLE option specifying the name for the new table.
Use a database tool to extract the DDL needed for the constraints (SQL Developer does the job). Edit the resulting script to match the name of the new class.
Execute the script.
If you need to do this programmatically you can use a statement like this:
DBMS_METADATA.GET_DDL('TABLE','PERSON') from DUAL;
I am going to create a lot of data scripts such as INSERT INTO and UPDATE
There will be 100,000 plus records if not 1,000,000
What is the best way to get this data into Oracle quickly? I have already found that SQL Loader is not good for this as it does not update individual rows.
Thanks
UPDATE: I will be writing an application to do this in C#
Load the records in a stage table via SQL*Loader. Then use bulk operations:
INSERT INTO SELECT (for example "Bulk Insert into Oracle database")
mass UPDATE ("Oracle - Update statement with inner join")
or a single MERGE statement
To keep It as fast as possible I would keep it all in the database.
Use external tables (to allow Oracle to read the file contents),
and create a stored procedure to do the processing.
The update could be slow, If possible, It may be a good idea to consider creating a new table based on all the records in the old (with updates) then switch the new & old tables around.
How about using a spreadsheet program like MS Excel or LibreOffice Calc? This is how I perform bulk inserts.
Prepare your data in a tabular format.
Let's say you have three columns, A (text), B (number) & C (date). In the D column, enter the following formula. Adjust accordingly.
="INSERT INTO YOUR_TABLE (COL_A, COL_B, COL_C) VALUES ('"&A1&"', "&B1&", to_date ('"&C1&"', 'mm/dd/yy'));"