Optimizer using MDC block index before accessing RID index
I have some large tables (over 100M rows on a non-partitioned
database) that each have at least one good candidate for an MDC
dimension. Am I right in assuming that if a query referencing an MDC
table contains two predicates, one on the MDC dimension, and the other
referencing a column in a RID index, the optimizer will only use the
RID index to examine pages within qualifying MDC extents/blocks?
Without MDC, I've often needed to include a commonly searched column
in multiple indexes in order to flexible searches. My plan for MDC is
to reduce the cost of many searches a...Stored procedure won't use index
We're using SQL Server 2000.
A very basic query on a 5 million row table would not work. If we
hard coded the one input parameter, the query used the foreign key
index and produced an instantaneous result. If, however, we pass the
parameter in as a parameter, the query doesn't use the index and takes
Declare @ID int
SET @ID = 17697
Select top 1 AccountID from tblAccounts where GroupID = @ID
We have fixed the problem by using an index hint to force the query to
use the index. However, my concern is - why is the index not
automatically used when we remove the...I want to use the index of an array (indicator) in block diagram programmatically.
Can I use the index of the array or must I build a pseudo index
control for the array?
If you want to programmatically set the index of the element displayed
in the upper left corner of the array indicator (=the number(s) in the
"index display" of the array indicator), create a property node for
the array and write to "property: Index Values".
(If this is not what you want, please use a few more sentences to
explain your problem).
u need set a local variable to the indicator
You can create a property node (right click on the terminal or the
index display on the front pa...simulink
In simulink, during the run time of the simulation, I am trying to compute a state from the first 5 seconds of the data and then use that state as an initial condition of the delay block.
Ex. I receive data for the first 5 seconds of the 60 sec simulation and by using these observations I compute the initial state of the my model(extended kalman filter). Then I want to use this initial state for the delay block of the recursion of the remaining 55 sec of simulation.
I couldn't find a way to do this, to specify this initial state in the delay block, it gives the error that this...C2000 DSP and Simulink : using a memory-stored variable as a block parameter
I've been toying with the C2000 toolbox for a little while
now, but I'm hitting a wall on this one.
What I'm trying to do is a PID controler whose parameters
can be changed by an external source or using a RTDX channel.
In fact this problem might arise for every block whose
parameters can't be specified from the outside.
Now I could create the controler with basic Simulink blocks,
but I want to use to more efficient PID-Controler from the
Since the C2000 doesn't have a workspace, I tried to use the
"Memory Copy" block from the Link for Cod...Using where; Using index vs Using where
What are the difference between the following statements, which one is
mysql> desc SELECT COUNT(*) as `cnt` FROM vote WHERE `ip` =
INET_ATON('127.0.0.1') AND (`addtime` > NOW() - INTERVAL 1 DAY) ;
| id | select_type | table | type | possible_keys | key |
key_len | ref | rows | Extra |
| 1 | S...Fo:Block can you check to see if a block contains any text by using the block id?
Is there any chance you can check if a fo:block with an id of "Tips"
contains any data.
The problem I'm having is creating a fo:block then for-each node within
one part of the xml I'm testing if scores match a particular high/Low
then printing Tips.
If there are no tips printed I would like to write a particular
statements which says "No Tips"
<Scale id="1" min="2" max="4">Statement 1</Scale>
<Scale id="2" min="2.4" max="3.5">Statement 2</Scale>
<Scale id="3...SVM resync -- all blocks or used blocks?
On our V20Z with 2x73 GB drives, a SVM resync after replacing a failed
disk takes about 75 minutes on fast disks.
We are curious why this is so, even though there is only 500 MB
allocated for the filesystems and 1 GB swap.
So we're wondering if SVM resync touches every single physical block
of the metadevice, regardless of allocated to data (in use) or not?
Dan Foster wrote:
> On our V20Z with 2x73 GB drives, a SVM resync after replacing a failed
> disk takes about 75 minutes on fast disks.
> We are curious why this is so, even though there is only 500 MB
> alloc...index is not used when exists clause is used
Here is the situation I met:
CREATE TABLE t1(f1 NUMBER, f2 VARCHAR2(20));
CREATE UNIQUE INDEX i1 ON t1 ( f1 );
CREATE TABLE t2(f1 NUMBER,f2 VARCHAR2(10), t1f1 NUMBER);
CREATE INDEX i2 ON t2(f1);
after explain following SQL
set f2 = 'abc'
where exists(select 1 from t2 where t1.f1 = t2.t1f1 and t2.f1 = 1);
0 UPDATE STATEMENT Optimizer=CHOOSE
1 0 UPDATE OF 'T1'
2 1 FILTER
3 2 TABLE ACCESS (FULL) OF 'T1'
4 2 TABLE ACCESS (BY INDEX ROWID) OF 'T2'
5 4 INDEX (RANGE SCAN) OF 'I2...