14 | 18 Jun 2013 @ 09:00 PDT | Database | Topic | How to determine whether TotalIOCount is significant or not | Hello,
After running a set of queries, it was found that, there are various values of TotalIOCount.
These values range from few hundreads to as high as 23 * 10^6.
On a system with 14 nod... |
13 | 19 Mar 2013 @ 09:39 PDT | Database | Topic | spool usage and spool space | Hi
If few SQL queries are run and highest spool usage value among all queries is obtained from DBQLOGTBL
Then does this mean that minimum spool should be set to highest spo... |
12 | 17 Dec 2012 @ 08:06 PST | Database | Topic | Skew Factor of Input and Output Tables of a Query | Hi
Question) Is it a a good idea to identify skew factor of input tables of a query before executing the same, especially for large data?
Question) If yes what is threshold beyond which skew... |
11 | 17 Dec 2012 @ 01:23 PST | Database | Topic | Interpretation of MaxAMPCPUTime and MinAMPCPUTime and difference between two | Hello,
If a query runs and shows following two values.
MaxAMPCPUTime = 265.968
MinAmpCPUTime = 245.072
Can one conclude that difference between these two is small i.e. ~ 20. It is less ... |
10 | 05 Nov 2012 @ 09:16 PST | Database | Reply | Slow Left Join query | Hello Ulrich,
All rows have same count value.
HASHROW(S_SK) Count(*)
------------------- -----------
6A330209 ... |
9 | 05 Nov 2012 @ 06:32 PST | Database | Reply | Slow Left Join query | Hi Ulrich,
select count(*) from misc.SPA_USAGE1 shows rows as 575,641,759
DataBaseName TableName skew_factor
1 misc  ... |
8 | 05 Nov 2012 @ 01:15 PST | Database | Topic | Slow Left Join query |
Following query takes 14 minutes. Table OUT_JOIN1 contains 200001 rows. Table
spa_usage1 contains app 54 million rows.
Stats are collected for ... |
7 | 20 Oct 2012 @ 03:27 PDT | Database | Topic | Explanation of fields in DBQLOGTBL and how to use info present in it | Hello,
Which document will contain explanation of fields in DBQLOGTBL?
Some of the fields of interest are as follows.
EstMaxRowCount, NumSteps, StatementType, WDID, LSN Integer, SLGMet etc.
&nb... |
6 | 11 Oct 2012 @ 11:51 PDT | Database | Reply | Slow left join query | Dieter
Thanks for your response.
It worked. It takes 10 minutes.
Nitin
|
5 | 03 Oct 2012 @ 01:38 PDT | Database | Reply | Slow left join query | CREATE TABLE MISC.table1
(
sub_sk NUMERIC(8) NOT NULL
TITLE 'sub_sk' ,
sub_id&n... |
4 | 29 Sep 2012 @ 01:47 PDT | Database | Reply | Slow left join query | Hello,
table1 index is sub_sk.
table2 index is contrib_sk.
Stats are collected on index, columns specified in ON and GROUP BY and table.
table2 is partitioned on usg_dt_sk.
5) We do a... |
3 | 28 Sep 2012 @ 02:51 PDT | Database | Topic | Slow left join query | Hello,
This is a left join query and it consumes more than 40 minutes.
select
table2.task_sk,
table1.sub_sk,
table1.sub_id,
sum(table2.items) as items,
 ... |
2 | 25 Sep 2012 @ 05:52 PDT | Database | Reply | Compression on Indexes | Thank you.
|
1 | 24 Sep 2012 @ 12:01 PDT | Database | Topic | Compression on Indexes | Hello,
Can compression be applied to indexes?
If so where can the syntax be found in documentation?
In database design document found that, compression can be applied to secondary indexes, join ... |