PostgreSQL has excellent support for evaluating JSONPath expressions against JSON data.
For example, this query returns true because the value of the nested field is indeed "foo".
select '{"header": {"nested": "foo"}}'::jsonb #? '$.header ? (#.nested == "foo")'
Notably this query does not reference any schemas or tables. Ideally, I would like to use this functionality of PostgreSQL without creating or connecting to a full database instance. Is it possible to run PostgreSQL in such a way that it doesn't have schemas or tables, but is still able to evaluate "standalone" queries?
Some other context on the project, we need to evaluate JSONPath expressions against JSON data in both a Postgres database and Python application. Unfortunately, Python does not have any JSONPath libraries that support enough of the spec to be useful to us.
Ideally, I would like to use this functionality of PostgreSQL without creating or connecting to a full database instance.
Well, it is open source. You can always pull out the source code for this functionality you want and adapt it to compile by itself. But that seems like a large and annoying undertaking, and I probably wouldn't do it. And short of that, no.
Why do you need this? Are you worried about scalability or ease of installation or performance or what? If you are already using PostgreSQL anyway, firing up a dummy connection to just fire some queries at the JSONB engine doesn't seem too hard.
I am going to use SQL terminology because I am new to Parse, apologies if that is confusing. I have a table in an app and in order to introduce new functionality I need to add a new column and set all the records to a default value. In SQL I would just run
update <table> set <column> = <value>;
Parse Server has MongoDB as the back end and I am not clear whether the correct approach is to directly access the MongoDB and run statements through the command line or if this would cause an issue with Parse. I found this helpful link for translating SQL syntax to MongoDB for that, https://docs.mongodb.com/manual/reference/sql-comparison/.
I also noticed that there were some tools, such as studio 3t, but the ones I saw all required expensive licenses. If direct MongoDB access is OK, any help understanding how to get to that would be helpful, I installed parse-server from the Bitnami stack on the AWS marketplace and to date I have only been interacting with it through the provided dashboard which doesn't have an "Update all records" option.
Right now my work around is to write a Swift script that runs the update in a loop, but I have to think that if I had millions or records instead of thousands this would be the incorrect approach. What is the proper environment and code to update my existing Parse server so that I can run something like the SQL above?
I'm new be to DB2/AS400. I know writing sql queries to insert/update in the database but not sure how could i perform same thing in DB2/AS400.Can any body guide me how could i write the sql insert/stored procedure queries in db2 database
STRSQL as suggested previously would work fine but it is a green screen (5250 emulation) option; if you are not familiar with that environment, I would recommend you use the 'Run SQL Script' function from either IBM i Access Client Solutions or IBM i Navigator, whichever is available to you.
On the AS400 command line issue the following command.
STRSQL
Start Here and this is typical IBM documentation. It leaves you guessing why am I here.
Is there any library where i can access mongodb by using sql like syntax.
Example
use db
select * from table1
insert into table1 values (a,b,c)
delete from table
select a,b,count(*) from table1 group by a,b
select a.field1,b.field2 from a,b where a.id=b.id
Thanks
Raman
The learning curve is small only if you are only doing extremely simple sql queries. If the extent of your SQL querying is "select * from X", then MongoDB looks like a brilliant idea to cut through all the too-complicated SQL. But if you need to perform left outer joins, test for null, check for ranges, subselects, grouping and summation, then you will soon end up with a round concave dent in your desk after being moved to Mongo. The sick punchline is that half the time, the thing you are trying to do can't be done in the Mongo interface. Mongo represents a bold new world where instead of databases doing things like aggregation and query optimization, it just stores data and all the magic is done by retrieving everything, slowly, storing it in app memory, and doing all that stuff in code instead.
YES!
A company called UnityJDBC makes a JDBC driver for mongodb. Unlike the mongo java driver, this JDBC driver allows you to run SQL queries against MongoDB and the driver is supported by any Java appliaction that uses JDBC.
to download this driver go to...
http://www.unityjdbc.com/mongojdbc/mongo_jdbc.php
Its free to download too!
hope this helps
MoSQL might satisfy your needs. It'll require you to run a new PostgreSQL instance but from there you can query your entire Mongo dataset with SQL.
"MoSQL imports the contents of your MongoDB database cluster into a PostgreSQL instance, using an oplog tailer to keep the SQL mirror live up-to-date. This lets you run production services against a MongoDB database, and then run offline analytics or reporting using the full power of SQL."
Have a look at this recent project: http://www.mongosql.com/. I've been looking at it over the last few weeks and it looks very promising.
For those of you who have questioned the usefulness of SQL against MongoDB, consider the large number of not-very-technical users in many organizations, like business analysts, who may know SQL, but don't want to make the leap to JavaScript and JSON. Tools like mongoSQL can help push the adoption of MongoDB in an organization.
There are a few solutions out there, but nearly all of them fail to truly represent the MongoDB data model in a way that the "relationally" minded ODBC/JDBC applications and users desire/require. A recent commercial product was released that addresses these challenges
ODBC:
http://www.progress.com/products/datadirect-connect/odbc-drivers/data-sources/mongodb
JDBC:
http://www.progress.com/products/datadirect-connect/jdbc-drivers/data-sources/mongodb
To address the need for ODBC/JDBC (SQL) access...While there are strong arguments for writing new applications using Mongo's clients, there is still a strong need in the marketplace for quality ODBC/JDBC and SQL based access to MongoDB. This need largely arises from all the reporting, analytic, and BI applications that rely on ODBC/JDBC connectivity and do not offer native integration with MongoDB.
Free NoSQL Viewer supports conversion of SQL queries to MongoDB shell syntax. Furthermore, in SQL Viewer you can even use SQL SELECT statements to query MongoDB collections data without knowing MongoDB query syntax. Check out NoSQL Viewer here www.spviewer.com/nosqlviewer.html
Mongodb and its current driver do not support direct SQL like syntax.
However, all operations are easily doable with the driver specific operations.
Here is a brief mapping of mongodb operations to corresponding SQL like query :
http://www.mongodb.org/display/DOCS/SQL+to+Mongo+Mapping+Chart
There are a couple projects underway to emulate a SQL interface for MongoDB. While they provide a familiar interface, in general they should be avoided. They operate on a fundamentally flawed premise in that they parse strings and translate them into method calls.
Once you work with MongoDB you will find the approach of using classes and methods a much more accessible interface as it works exactly like all other parts of your application. Yes there is a small learning curve as you first start, but for the most part, the interface in MongoDB works how you would expect it to.
We have a software solution that involves syncing some data between a Progress database and SQL server. Unfortunately, we do not have any Progress gurus in house, so I'm working kinda blind here and would welcome any advice that is on offer.
For the workflow that is already in place, what would work very well for us is the ability to do an external call to insert a row into an SQL database from an within ABL procedure's 'for each' loop.
Is anyone able to direct me to any code snippets or articles that might help me achieve this?
Many thanks,
In case your SQL database is MS SQL Server, you might want to have a look at OpenEdge DataServer for Microsoft SQL Server (web.progress.com/en/openedge/dataserver-microsoft.html, documentation.progress.com/output/OpenEdge102b/pdfs/dmsql/dmsql.pdf).
The DataServer provides you with ABL access to a non-Progress database so you can use standard Progress statements, e.g. CREATE to add new records or FOR EACH to retrieve query results.
OpenEdge DataServers are also available for Oracle (using Oracle Call Interface), DB2 and Sybase (using ODBC). The DataServer for MS SQL Server uses ODBC behind the scenes as well. web.progress.com/docs/datasheets/openedge/openedge_dataservers.pdf
You dont need the dataserver, connection with ADODB works fine in ABL, you can even call stored-procedures with the command object, the user you connect with will have to be granted EXEC rigths on the SQL-Server to do that.
I'm not a Progress guru, but I did do some work in it for awhile. AFAIK there is no way to have ABL code connect to a non-Progress database (part of that whole vendor lock-in strategy Progress Corp. leverages).
Your best bet is probably to have the ABL code serialize the records to XML, and use something like ActiveMQ (or even a plain socket or named pipe/FIFO depending on your setup) to send them to a program written in a more capable language to do the SQL insert.