Is there any way to query tables from a Microsoft Access .mdb database using Ruby on a Linux platform?
I would like to read directly, not convert to Mysql then read. In fact, being more specific, I would like to query the tables i.e. add filters etc
Related
As the title suggests, I'm attempting to open an SDF/MSSQL CE database in GoLang. Is this possible?
The GoLang Libraries I've found do not appear to suppot MSSQL CE database connections.
I hope this is not a duplicate, but I can not find info online
I'm afraid it would hardly be possible to work with these files directly as they merely are on-disk storage format, and note that MSSQL DBs of all flavors use .sdf as the extension of the file names of their DBs, so by itself they mean nothing.
OTOH, one direct way to approach this problem would be using
OLE DB layer.
You can also try to use
https://github.com/denisenkom/go-mssqldb
to connect to MSSQL Express instance like that:
sqlserver://sa#localhost/SQLExpress?database=master&connection+timeout=30
I am Oracle Data base Bigginner. I am Confusing with this two words sql * plus and sql loader,Any one Tell me the difference between SQL loader and SQL * PLUS?
From the documentation:
SQLPlus is an interactive and batch query tool that is installed with every Oracle Database Server or Client installation. It has a command-line user interface, a Windows Graphical User Interface (GUI) and the iSQLPlus web-based user interface.
SQLPlus has its own commands and environment, and it provides access to the Oracle Database. It enables you to enter and execute SQL, PL/SQL, SQLPlus and operating system commands to perform the following:
Format, perform calculations on, store, and print from query results
Examine table and object definitions
Develop and run batch scripts
Perform database administration
You can use SQLPlus to generate reports interactively, to generate reports as batch processes, and to output the results to text file, to screen, or to HTML file for browsing on the Internet. You can generate reports dynamically using the HTML output facility of SQLPlus, or using the dynamic reporting capability of iSQLPlus to run a script from a web page.
SQLLoader loads data from external files into tables of an Oracle database. It has a powerful data parsing engine that puts little limitation on the format of the data in the datafile. You can use SQL*Loader to do the following:
Load data across a network if your data files are on a different system than the database.
Load data from multiple datafiles during the same load session.
Load data into multiple tables during the same load session.
Specify the character set of the data.
Selectively load data (you can load records based on the records' values).
Manipulate the data before loading it, using SQL functions.
Generate unique sequential key values in specified columns.
Use the operating system's file system to access the datafiles.
Load data from disk, tape, or named pipe.
Generate sophisticated error reports, which greatly aid troubleshooting.
Load arbitrarily complex object-relational data.
Use secondary datafiles for loading LOBs and collections.
Use either conventional or direct path loading. While conventional path loading is very flexible, direct path loading provides superior loading performance.
SQL* Plus is installed with every Oracle Database Server or Client installation. It has a command-line user interface, a Windows Graphical User Interface (GUI) and the iSQLPlus web-based user interface.
SQL Loader loads data from external files into tables of an Oracle database.It can also be Load data across a network.
SQL*plus is something that provides an access to the Oracle Database.
SQL Loader is you are loading the external data or files from your disk to Oracle database.
I'd like to be able to read a SAS dataset with Ruby. Does anyone know of a way to do this?
If you have access to a local instance of SAS or to a SAS/SHARE server, you can use the SAS ODBC driver to connect to and read from SAS data libraries. I run a SAS/SHARE server myself and access it from Excel all the time.
See the SAS ODBC Driver User Manual for the version of SAS you are using for more info.
SAS dataset files are coded in a proprietary format. If you have access to SAS, you can export the dataset as a delimited text file, and then read that with Ruby. If you don't have access to SAS, you could look into getting StatTransfer, but it's not cheap.
It is possible to do what you want.
You could use the ruby gem Pandas.rb to
# Untested
require 'pandas'
df = Pandas.read_sas("./path/to/dataset.sas7bdat")
Alternatively, with some development effort you could implement the logic in Pandas sas7bdat.py and xport.py
I have the Remedy odbc driver installed on my machine. I am able to pull down data from Remedy via excel just fine specifying this driver in my connection.
Is there any way I could use this driver from within Ruby / Ruby on rails to connect to and read from the DB?
Many thanks!
I have not found a way to use the Remedy ODBC driver from Ruby. Also, I am suspecting that using the driver which seems to be quite antiquated and is already throwing some arcane errors when used from Excel might not be simple to use.
I was able to connect through R via RODBC and thus an R script that would pull the data for you and write to CSV might be a solution.
What I am actually using - which to my mind is the simplest way of achieving this - is talking directly to the Remedy SQL backend. All that you will have to do is parse the data upon pulling it from DB which is very easy to set up (priorities, service types, statuses are stored as integers and not actual names and timestamps are in epoch format).
In our legacy SW we make our own wrapper classes to perform DB command and query. Now we want to switch to .NET 4 and want to use LINQ to SQL. But I am not quite sure whether it is mandatory to add a .mdf file to make it work.
Because we have our database service running already, and we would like to keep using the database on it(because our customers would want to keep using their databases), obviously we don't want to distribute a brand-new database file with our SW. But every article I found about LINQ to SQL says that I need to add a .mdf file to the project to make it work. So how should we do that? Can we use LINQ without assigning any database in the development?
Thanks!
LINQ to SQL doesn't require a local .MDF file in a project to work. You can generate LINQ to SQL classes against an existing remote database. Just connect to the server in the Server Explorer and drag tables to the LINQ to SQL designer.
Many people use the .MDF file in examples simply because it's a small, self-contained database. It's a convenience to the demo, not a requirement.
Additionally, it's possible to create a .MDF file with a schema that matches a remote database and work against that file during development but simply switch connection strings to go from a local file to a remote database.