Tip Bank

DevX - Software Development Resource

Compound key

Question: I want to use a unique compound key, with a string columns and a numeric column, in my table. Since Blaze does not support compound keys, I will have

DevX - Software Development Resource

Finding Two Equal Sets of Data

Question: [Joe Celko’s Equal Sets Puzzle]Set theory has two symbols for subsets. One is a “horseshoe” on its side, which means that set A is contained within set B and

DevX - Software Development Resource

Data Replication

Question: I’ve heard several of the arguments in favor of a server that supports datareplication. What are the potential problems? Answer: For our readers, the advantages of data replication [creating

DevX - Software Development Resource

COUNT Function: Getting a Series

Question: What is the syntax to get a series of “counts” on a table? An exampleof what I am trying to do is as follows:SELECT col1 = COUNT(tstfield1=’X’),col2 = COUNT(tstfield2=’Y’)

DevX - Software Development Resource

Flushing and Locking

Question: How can I set the flushing of rows to the database or the locking strategy used by Power Objects? Answer: Oracle Power Objects ‘supports’ two ways that rows can

DevX - Software Development Resource

Pattern Matching

Question: How can I use SQL to specify a query like the example below: select * from mytable where column like ‘a[bc]’This should match both “ab” and “ac” but not

DevX - Software Development Resource

Checking for a lost connection

Question: I want to periodically check to see if a user’s database connection has been lost. How can I? Answer: First of all, a solution. You can implement periodic ‘polling’