I'm using oracle 11g and I'm loading data into the database using the sql loader which are invoked through the unix scripts. I want to select some rows of data and write the data into the file using shell scripts. Is it possible to write a shell script for the same.
Here is an excellent tutorial which clearly explain how to execute a query from UNIX
Ultimately what he does is login into Oracle i.e., setup a session for Oracle and read a query that needs to be executed and execute that query and do what ever operation needed.
Instead of reading the query from the user we could read it from a file or even hardcode it there itself as per our need.
Blog which explain about usage of Oracle query in Shell script
Related
In Oracle or other DBs, we have a concept of PL/SQL package where we can package multiple queries/procedures and call them inside a UNIX script. In case of Hive queries, what's the process used to package and automate the query processing in actual production environments.
If you are looking to automate the execution of numerous Hive queries, the hive or beeline CLI (think sqlplus with Oracle) allows you to pass a file containing one or more commands such as multiple inserts, select, create tables, etc. The contents of said file can be created programmatically using your favorite scripting language like python or shell.
See the "-i" option in this documentation: https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Cli
In terms of a procedural language, please see:
https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=59690156
HPL/SQL does have a Create Package option but if whatever you are trying to achieve is scripted outside of HPL/SQL (e.g. python, shell), you can 'package' your application in accordance with scripting best practices of your selected language.
To run mutilpe queries simply write it down one after another in a file (say 'hivescript.hql') and then it can be run from bash by simply calling it through beeline or hive shell
beeline -u "jdbc:hive2://HOST_NAME:10000/DB" -f hivescript.hql
I am using JRuby to connect to Hive, which is happening successfully. Now I want to create tables, but instead of writing the create statement as a parameter to execute() method, I want to call a ddl file that has the table definition.
I cannot take the file contents and use them because they are usually more than one statement before the actual table creation (i.e. CREATE DATABASE IF NOT EXISTS, CREATE TABLE IF NOT EXISTS ..)
Is there a command that I can use through my JDBC connect that take the ddl file and executes it?
As per my knowledge there is no direct way with JDBC API to do an operation similar to hive -f ,
option 1)
you can parse your SQL file and write a method to execute the commands sequentially (or) use third party code,
here is one reference http://www.codeproject.com/Articles/802383/Run-SQL-Script-sql-containing-DDL-DML-SELECT-state
option 2) If your client environment where Jruby code is running also supports hive, write a shell script which can connect to remote JDBC and run SQL with beeline which will make remote Thrift calls
Reference : https://cwiki.apache.org/confluence/display/Hive/HiveServer2+Clients
I tried searching online but was unable to find anything pertaining to my requirements.
I am new to Teradata.
In our team Teradata jobs are used to call the ksh which in turn calls the procedure to run at a scheduled time.
I want to understand how exactly does this calling works? How does a job call a KSH and then how does a KSH call a procedure in turn.
Your help would be much appreciated.
At a very basic level UNIX has a scheduler mechanism called cron. Users with sufficient privilege on the UNIX server can use cron to run jobs at a scheduled time by defining a crontab. Your crontab can call UNIX commands or in many cases a shell script (ksh in your example) to perform a complex set of operations. In many production environments jobs may be scheduled using an enterprise platform instead of many independent crontab files across many users and many servers in the data center.
As this pertains to Teradata, the ksh is likely invoking a Teradata utility such as BTEQ to logon to the database and execute a stored procedure, macro, or set of SQL statements contained within the BTEQ script. Once the BTEQ script has completed a return code is sent to the ksh script to account for any error handling should an error occur within the BTEQ script or an unhandled/handled error within the stored procedure.
You can use your search engine of choice to read up on how to develop UNIX shell scripts (Korn, Bash, etc.) and how Teradata utilities such as BTEQ work. If you have a more discrete question about something in your environment feel free to post a separate question here with the appropriate tags in the question to target the audience who can best help you.
I'm developing an application which runs on an Oracle database. I'm now in the process of creating an installation package which will contain some SQL scripts containing the default data that comes with the program.
Some of the tables have BLOB columns which need to contain MS Word documents. I'm not sure how to get these BLOBs into the SQL scripts. I know I could do it through Data Pump, but it is a requirement that all database stuff is included in plain text SQL files.
Does anyone know how to get these BLOBs into an SQL script which the client can just run?
Thanks!
I solved this problem by creating a PHP script that is run as part of the installation process - it loops through all my word documents and inserts them into the database. I would still rather have SQL scripts or something similar but this works for now.
How to get the output of a query into a flat file using Oracle on UNIX?
For example:
I have a TEST table; I want to get the content of the TEST table into a flat file and then store the output in some other folder in .txt format.
See Creating a Flat File in the SQL*Plus User's Guide and Reference.
in the oracle SQLplus terminal you could type
spool ;
run your query
spool off;
Now the would contain the results of the query.
In fact it would contain all the output to the terminal since the execution of the spool command till spool off.
If you have access to directories on the database server, and authority to create "Directory" objects in Oracle, then you have lots of options.
For example, you can use the UTL_FILE package (part of the PL/SQL built-ins) to read or write files at the operating system level.
Or use the "external table" functionality to define objects that look like single tables to Oracle but are actually flat files at the OS level. Well documented in the Oracle docs.
Also, for one-time tasks, most of the tools for working SQL and PL/SQL provide facilities for moving data to and from the database. In the Windows environment, Toad's good at that. So is Oracle's free SQLDeveloper, which runs on many platforms. You wouldn't want to use those for a process that runs every day, but they're fine for single moves. I've generally found these easier to use than SQL*Plus spooling, but that's a primitive version of the same functionality.