http://asktom.oracle.com These are the most recently asked questions on Ask Tom en-us Copyright 1999-2006, Oracle Corporation http://asktom.oracle.com/i/asktom2.gif http://asktom.oracle.com 50 50 Ask Tom is a forum where Tom Kyte, Oracle's Database Guru, answers questions regarding Oracle technology, specifically the database. http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:3233191441609 <code>Hi Tom, On page 130-131 of your book, "expert one-on-one Oracle," you gave an example of two sessions querying and inserting into tables a and b. The result is that both tables contain a row with the value zero in them. My question is that ... http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:275215756923 <code>Tom, Would you tell me what snapshot too old error. When does it happen? What's the possible causes? How to fix it? Thank you very much. Jane </code> http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:273215737113 <code>Tom, When updating a column with an update-statement, the value of some records (records that don't need to be updated), are changed into the value NULL. I use the next statement: update table name B set columnname = ... http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:708300100346931976 Dear Tom, With 11g Oracle now seems to use dbms_epg as the default engine for APEX. Could you elaborate a little on the differences and give us some hints on if and how to migrate existing Apache/mod_plsql (but not APEX) application to dbms_epg. ... http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:974699100346868838 Hi Tom, When an user is created using "create user" it will create a user as well as a schema with the same name as user. Also, there is a way to create only schema as well, using "create schema". But how do I create a user without and associated ... http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:400219009850 <code>Hi Tom, by mistake, we had delete one datafile and now the DB could not be open, but can be mount. Unfortunately, we are running our DB in NOARCHIVE mode and we don't hav a backup too. b'coz we are fools (I just came to know that.) plz. h... http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:2196162600402 <code>Hi Tom, Is there anyway that I can just use SQL to do string concatenation on a VARCHAR2 field much the same way that a SUM() function is used on a NUMBER field. For example, SELECT SUM(revenue), department FROM sales_table ... http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:6407993912330 <code>Good Morning Tom. I need your expertise in this regard. I got a table which contains millions or records. I want to update and commit every time for so many records ( say 10,000 records). I dont want to do in one stroke as I may end up i... http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:489772591421 <code>hi tom can u explain me in detail about "start with connect by" sql statement (tree structure).i know there is documentatin but it is very confusing. </code> http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:232814159006 <code>Tom, How can we display PDF files stored in the database, using htp.p (OAS PL/SQL cartridge )calls and dbms_lob ? We are developing a document archival and display app. Using ctxload, I can upload the files. Now, I would like to display th...