You can change this in preferences: From Oracle SQL Developer’s menu go to: Tools > Preferences. From the Preferences dialog, select Database > NLS from the left panel. From the list of NLS parameters, enter DD-MON-RR HH24:MI:SS into the Date Format field. Save and close the dialog, done! Here is a screenshot:
Your table is already locked by some query. For example, you may have executed “select for update” and have not yet committed/rollbacked and fired another select query. Do a commit/rollback before executing your query.
It’s a sort of dummy table with a single record used for selecting when you’re not actually interested in the data, but instead want the results of some system function in a select statement: e.g. select sysdate from dual; See http://www.adp-gmbh.ch/ora/misc/dual.html
Version I am using Update 5th May 2012 Jeff Smith has blogged showing, what I believe is the superior method to get CSV output from SQL Developer. Jeff’s method is shown as Method 1 below: Method 1 Add the comment /*csv*/ to your SQL query and run the query as a script (using F5 or … Read more
SQL Developer can start a new tab every time you select a database object to view; but, you will have to close the tab manually. Set this in: Tools->Preferences->Database->ObjectViewer->Automatically Freeze Object Viewer Windows
As for now, they are synonyms. VARCHAR is reserved by Oracle to support distinction between NULL and empty string in future, as ANSI standard prescribes. VARCHAR2 does not distinguish between a NULL and empty string, and never will. If you rely on empty string and NULL being the same thing, you should use VARCHAR2.
I had this issue and the fix was to make sure in tnsnames.ora the SERVICE_NAME is a valid service name in your database. To find out valid service names, you can use the following query in oracle: select value from v$parameter where name=”service_names” Once I updated tnsnames.ora to: TEST = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS … Read more
From Ask Tom You should consider a schema to be the user account and collection of all objects therein as a schema for all intents and purposes. SCOTT is a schema that includes the EMP, DEPT and BONUS tables with various grants, and other stuff. SYS is a schema that includes tons of tables, views, … Read more
Create a diagram for existing database schema or its subset as follows: Click File → Data Modeler → Import → Data Dictionary. Select a DB connection (add one if none). Click Next. Check one or more schema names. Click Next. Check one or more objects to import. Click Next. Click Finish. The ERD is displayed. … Read more