Razzak, Thanks for that, but I note that if I reduce the length of the text (including the three 'numeric' characters at the start) I get different values from the Hash command. Does IHASH need an alternative function RHASH (a real value) to cater for longer strings ?
R>sel company nvhash from qt company nvhash ---------------------------------------- ---------- 250spirosetplain 522109344 - these are unique 350spirosetplain 522109345 - these are unique 150spirosetplain 522109347 - these are unique Regards, John Docherty -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of A. Razzak Memon Sent: Tuesday, 22 February 2005 11:01 a.m. To: RBG7-L Mailing List Subject: [RBG7-L] - Re: IHASH Command At 04:51 PM 2/21/2005, John Docherty wrote: >Razzak, > >Data from my new table, qt is as follows - I added the two 'problem' >rows, which I have since found are not unique in my data, as follows. > >R>sel company nvhash from qt > company nvhash > ---------------------------------------- ---------- > 250Computer Warehouse - II 507350364 > 350Microtech University 935204673 > 450Industrial Computers Inc. 524758399 > 550Computer Mountain Inc. 333077815 > 250spirosetplaininsulated 963864368 > 350spirosetplaininsulated 963864368 John, The reason you have the SAME IHASH value for the last two records is that both "TEXT" values (strings) are exactly the same. FYI, the IHASH function is designed to create effective integer keys from the text columns. The function, IHASH, converts the entire TEXT value, or just a specified number of TEXT characters. Hope that explains! Very Best R:egards, Razzak. -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.306 / Virus Database: 266.2.0 - Release Date: 21/02/2005
