Oracle SQL Developer + AWS Redshift : Can only view tables - oracle-sqldeveloper

I've gotten SQL Developer to be able to connect to my RedShift cluster but I can only see the tables. I can't see any of the views? Does anyone know if that's possible or if I should just be considering a different tool to work with Redshift?
If I use other tools (i.e. Aginity) I can see the views so I know it's not a DB permission thing, it must be a JDBC+SQL-Develop thing.
What tool do you use for RedShift?

Our redshift support is presented for a singular use case: copying/moving your data to the Oracle Autonomous Data Warehouse (ADW)
Can you connect and browse to a redshift instance? Yes. But that's not the desired use case.

Related

How to set Postgres tables to use columnar storage using dbt?

We are using dbt to manage our data models in MSSQL, and we are considering moving to PostgreSQL Citus.
I'm not clear on how I could use Citus's features via dbt? I'm thinking specifically of data compression and columnar storage.
Any ideas?
TBH, I don't have any experiences with dbt.
However, given that dbt docs state that they support PostgreSQL, and Citus Columnar is a table-access-method level abstraction that doesn't require any changes to the queries(*), I wouldn't expect any compatibility issues when combining both.
My guess is that after creating your tables with USING columnar option, then you can just follow dbt docs for the rest.
(*): You might still want to have a look into that page to see what Citus Columnar does or doesn't support atm.
https://github.com/citusdata/citus/tree/master/src/backend/columnar#introduction
was wondering if you had any updates on how this process has gone for you?
I'm looking to implement DBT at my company and was considering postgres/citus as well.
I believe you could use a combination of pre-hook/post-hook dbt functions and materializing incrementally instead of the table or view method.
Thinking is either pre-hook create columnar table and use the dbt incremental update, or materialize as view/table then post-hook SELECT alter_table_set_access_method('table_name', 'columnar');

streaming PostgreSQL tables into Google BigQuery

I would like to automatically stream data from an external PostgreSQL database into a Google Cloud Platform BigQuery database in my GCP account. So far, I have seen that one can query external databases (MySQL or PostgreSQL) with the EXTERNAL_QUERY() function, e.g.:
https://cloud.google.com/bigquery/docs/cloud-sql-federated-queries
But for that to work, the database has to be in GCP Cloud SQL. I tried to see what options are there for streaming from the external PostgreSQL into a Cloud SQL PostgreSQL database, but I could only find information about replicating it in a one time copy, not streaming:
https://cloud.google.com/sql/docs/mysql/replication/replication-from-external
The reason why I want this streaming into BigQuery is that I am using Google Data Studio to create reports from the external PostgreSQL, which works great, but GDS can only accept SQL query parameters if it comes from a Google BigQuery database. E.g. if we have a table with 1M entries, and we want a Google Data Studio parameter to be added by the user, this will turn into a:
SELECT * from table WHERE id=#parameter;
which means that the query will be faster, and won't hit the 100K records limit in Google Data Studio.
What's the best way of creating a connection between an external PostgreSQL (read-only access) and Google BigQuery so that when querying via BigQuery, one gets the same live results as querying the external PostgreSQL?
Perhaps you missed the options stated on the google cloud user guide?
https://cloud.google.com/sql/docs/mysql/replication/replication-from-external#setup-replication
Notice in this section, it says:
"When you set up your replication settings, you can also decide whether the Cloud SQL replica should stay in-sync with the source database server after the initial import is complete. A replica that should stay in-sync is online. A replica that is only updated once, is offline."
I suspect online mode is what you are looking for.
What you are looking for will require some architecture design based on your needs and some coding. There isn't a feature to automatically sync your PostgreSQL database with BigQuery (apart from the EXTERNAL_QUERY() functionality that has some limitations - 1 connection per db - performance - total of connections - etc).
In case you are not looking for the data in real time, what you can do is with Airflow for instance, have a DAG to connect to all your DBs once per day (using KubernetesPodOperator for instance), extract the data (from past day) and loading it into BQ. A typical ETL process, but in this case more EL(T). You can run this process more often if you cannot wait one day for the previous day of data.
On the other hand, if streaming is what you are looking for, then I can think on a Dataflow Job. I guess you can connect using a JDBC connector.
In addition, depending on how you have your pipeline structure, it might be easier to implement (but harder to maintain) if at the same moment you write to your PostgreSQL DB, you also stream your data into BigQuery.
Not sure if you have tried this already, but instead of adding a parameter, if you add a dropdown filter based on a dimension, Data Studio will push that down to the underlying Postgres db in this form:
SELECT * from table WHERE id=$filter_value;
This should achieve the same results you want without going through BigQuery.

In DBeaver, how can I run an SQL union query from two different connections..?

We recently migrated a large DB2 database to a new server. It got trimmed a lot in the migration, for instance 10 years of data chopped down to 3, to name a few. But now I find that I need certain data from the old server until after tax season.
How can I run a UNION query in DBeaver that pulls data from two different connections..? What's the proper syntax of the table identifiers in the FROM and JOIN keywords..?
I use DBeaver for my regular SQL work, and I cannot determine how to span a UNION query across two different connections. However, I also use Microsoft Access, and I easily did it there with two Pass-Through queries that are fed to a native Microsoft Access union query.
But how to do it in DBeaver..? I can't understand how to use two connections at the same time.
For instance, here are my connections:
And I need something like this...
SELECT *
FROM ASP7.F_CERTOB.LDHIST
UNION
SELECT *
FROM OLD.VIPDTAB.LDHIST
...but I get the following error, to which I say "No kidding! That's what I want!", lol... =-)
SQL Error [56023]: [SQL0512] Statement references objects in multiple databases.
How can this be done..?
This is not a feature of DBeaver. DBeaver can only access the data that the DB gives it, and this is restricted to a single connection at a time (save for import/export operations). This feature is being considered for development, so keep an eye out for this answer to be outdated sometime in 2019.
You can export data from your OLD database and import it into ASP7 using DBeaver (although vendor tools for this are typically more efficient for this). Then you can do your union as suggested.
Many RDBMS offer a way to logically access foreign databases as if they were local, in which case DBeaver would then be able to access the data from the OLD database (as far as DBeaver is concerned in this situation, all the data is coming from a single connection). In Postgres, for example, one can use a foreign data wrapper to access foreign data.
I'm not familiar with DB2, but a quick Google search suggests that you can set up foreign connections within DB2 using nicknames or three-part-names.
If you check this github issue:
https://github.com/dbeaver/dbeaver/issues/3605
The way to solve this is to create a task and execute it in different connections:
https://github.com/dbeaver/dbeaver/issues/3605#issuecomment-590405154

Synchronize between an MS Access (Jet / MADB) database and PostgreSQL DB, is this possible?

Is it possible to have a MS access backend database (Microsoft JET or Access Database Engine) set up so that whenever entries are inserted/updated those changes are replicated* to a PostgreSQL database?
Two-way synchronization would be nice, but one way would be acceptable.
I know it's popular to link the two and use one as a frontend, but it's essential that both be backend.
Any suggestions?
* ie reflected, synchronized, mirrored
Can you use Microsoft SQL Server Express Edition? Or do you have to use Microsoft Access Database Engine? It's possible you'll have more options using MS SQL express, like more complete triggers and logging.
Either way, you're going to need a way to accumulate a log of changed rows from the source database engine, and a program to sync them to PostgreSQL by reading the log and converting it into suitable PostgreSQL INSERT, UPDATE and DELETE statements.
You could do this by having audit triggers in MADB/Express insert a row into an audit shadow table for every "real" table whenever it changed, including inserting special "row deleted" audit entries. Then your sync program could connect to both MADB/Express, read the audit tables, apply the changes to PostgreSQL, and empty the audit tables.
I'll be surprised if you find anything to do this out of the box. It's one area where Microsoft SQL Server has a big advantage because of all the deep Access and MADB engine integation to support the synchronisation and integration features.
There are some ETL ("Extract, Transform, Load") tools that might be helpful, like Pentaho and Talend. I don't know if you can achieve the desired degree of automation with them though.

How to transfer or copy tables of DB2 to oracle database

I want to transfer some tables of DB2 to oracle daily for accessing them from web page,
But I don't know commands of DB2. How to do this?
I want this action should perform on database daily on particular time, so is there any tool is available to do this operation. And for writing the program for operating above query which programming language should I use? I am using windows XP.
I think Change Data Capture is used to replicate DML from one database to other databases continuously.
However, what you need is to transfer some data at a particular time each day, thus CDC could be too heavy for that.
You could do a simply "db2 export", and then you could import the generated file from Oracle.
There should be an option to create an adapter in Oracle that permits to query DB2 tables. The opposite is called federation in DB2 (InfoSphere Information Server) that permits to query Oracle tables.
Export http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/topic/com.ibm.db2.luw.admin.cmd.doc/doc/r0008303.html
CMD examples http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/topic/com.ibm.db2.luw.admin.dm.doc/doc/r0004567.html
Check this link
http://blogs.oracle.com/warehousebuilder/entry/simple_change_data_capture_from_db2_table_to_oracle_table
In 11.2 releases, Change Data Capture (CDC) can be done by code template mapping. This allows users to capture the data changes from heterogeneous data source, and load into the target across different platforms.