Subject | RE: [firebird-support] Strange FIRST n SKIP m + Function behaviour in FB 2.5 Beta 2 |
---|---|

Author | Kim Sandell (Celarius) |

Post date | 2009-09-22T23:14:26Z |

Thanx,

the reason I was trying to use the statements was to calculate the Median of

a data-range.

I've now solved it as:

/* For Even count of values (Data range count is 20000 values)*/

SELECT FIRST 1 SKIP 10000 DUR_TOTAL AS Median FROM HTTP_Events ORDER BY

DUR_TOTAL

/* For UnEven count of values (Data range count is 20001 values)*/

SELECT AVG(DUR_TOTAL) AS Median FROM

(SELECT FIRST 2 SKIP 10000 DUR_TOTAL FROM HTTP_Events ORDER BY DUR_TOTAL)

-Kim

From: firebird-support@yahoogroups.com

[mailto:firebird-support@yahoogroups.com] On Behalf Of Alan McDonald

Sent: 23. syyskuuta 2009 00:18

To: firebird-support@yahoogroups.com

Subject: RE: [firebird-support] Strange FIRST n SKIP m + Function behaviour

in FB 2.5 Beta 2

don't use first and skip with aggregate selects.

Alan

[Non-text portions of this message have been removed]

the reason I was trying to use the statements was to calculate the Median of

a data-range.

I've now solved it as:

/* For Even count of values (Data range count is 20000 values)*/

SELECT FIRST 1 SKIP 10000 DUR_TOTAL AS Median FROM HTTP_Events ORDER BY

DUR_TOTAL

/* For UnEven count of values (Data range count is 20001 values)*/

SELECT AVG(DUR_TOTAL) AS Median FROM

(SELECT FIRST 2 SKIP 10000 DUR_TOTAL FROM HTTP_Events ORDER BY DUR_TOTAL)

-Kim

From: firebird-support@yahoogroups.com

[mailto:firebird-support@yahoogroups.com] On Behalf Of Alan McDonald

Sent: 23. syyskuuta 2009 00:18

To: firebird-support@yahoogroups.com

Subject: RE: [firebird-support] Strange FIRST n SKIP m + Function behaviour

in FB 2.5 Beta 2

> Hi,but the first one is going to be your min and you skip it...

>

> I've got a few SQL Queries that behave strangely with FB v2.5 Beta 2:

>

> 1st the OK situations:

>

> SELECT FIRST 3 Dur_Total FROM HTTP_Events

> gives 3 result rows: 0.5575, 1.2298, 0.7567

>

> SELECT FIRST 2 SKIP 1 Dur_Total FROM HTTP_Events

> gives 2 result rows: 1.2298, 0.7567

>

> Now the problem statements:

>

> SELECT FIRST 2 SKIP 1 Min(Dur_Total) FROM HTTP_Events

> gives 0 result rows????? Correct answer would be 1 row with value

> 0.7567

> The same happens with MIN(), MAX(), AVG(), SUM() etc...

> Event COUNT() gives an empty result...

don't use first and skip with aggregate selects.

Alan

[Non-text portions of this message have been removed]