How do I write Oracle SQL expression (using TOAD) that inserts rows into a table from a select statement, ie "Insert into table(field 1, field 2, field 3, etc) values(select field1, field2, field3 from tables where conditions)"?
Why doesn't the Oracle optimizer use my index?
Querying too much data
Most Oracle developers know that an index is useful when you can use it to restrict your result set to a small number of the total rows in a table.
So, the obvious side…
This post first appeared at Oracleinaction (http://oracleinaction.com/undo-and-redo-in-oracle/)by Anju Garg (Myself).
I will demonstrate that undo for DML’s is stored both in undo tablespace and online redo logs. Then, we will analyze the reaso…