Chang the WHERE clause

hi,
I want to change the Where clause used in the block, to change runtime in the
forms, need help.
Thanks.

You can use set_block_property that triggered from a button
(When a button pressed):
1. With default_where parameter:
SET_BLOCK_PROPERTY('blockname', DEFAULT_WHERE, 'column = ''value''');
SET_BLOCK_PROPERTY('emp', DEFAULT_WHERE, 'gender=''M''');
2. With query_data_source_name parameter:
PROCEDURE codevisibility IS
qdsn varchar2(100);
BEGIN
     go_block('myblock');
     clear_block;
     IF :urutblok.options = 'I' THEN
          qdsn := ' (SELECT * FROM FERRY.mytab WHERE '
               ||' CODE = '||:blk.code
               ||' AND CODE2 = '||'''I'''||')';
     SET_BLOCK_PROPERTY('myblock',query_data_source_name, qdsn );
     ELSIF :urutblok.options = 'P' THEN
          qdsn := ' (SELECT * FROM FERRY.mytab WHERE '
               ||' CODE = '||:blk.code
               ||' AND CODE2 = '||'''P'''||')';
     SET_BLOCK_PROPERTY('myblock',query_data_source_name, qdsn );
END IF;
     EXECUTE_QUERY;
END;
rgds,
ferry.

Similar Messages

Dynamically changing the WHERE clause in detail VO in Master Detail

Hi, I want to develop a search functionality, results will be in a table, which will have an inline table displaying the details per row found.
I have a MD defined trough viewlink. I do change the master VO at runtime (set the entire SQL), based on the criteria entered by the user.
Is there a way to change the VO at the detail end of the link at runtime - that is what I haven't been able to do.
I have read that the ADF framework creates internal VO for each master row, whenever accessed trough accessor (which is not I am trying to do). I haven't been able to find a way to get a hold of the REAL VO at the detail end and have its WHERE clause changed.
Changes to the "VO instance in AM" (same one used as a definition in the detail end in the ViewLink def) does not seem to reflect the detail VO.
I have a MasterView, DetailView, MasterDetailLink (MasterView->DetailView).
MasterDetailLink is used to create a table with inline detail table. At runtime:
1.get MasterView (from AM), change query trough setQuesry() - works.
2.get DetailView (from AM), change query trough addWhereClause() - does not work (no exceptions) - the results I am getting DO NOT reflect the conditions of the where clause, I mean the clause have not been addedd.
I 've looked at the logs (debug enabled) and it seems to me that there no "activities" related to the detail VO, even after the where clause of the VO from step 2 is changed.
Looks like there is a separate VO which I would like to get a hold of :)
Thanks, and sorry for the long explanation

After you have added a new where clause on the detail VO, try re-executing VO's query by DetailVO.executeQuery()
If it doesn't work try re-executing the MasterVO's query after you have added the where clause on the detail

Changing the where clause

Hi all,
Can anyone suggest an appropriate answer for this
I want to change the where condition in Reports (Developer 2000) dynamically (in runtime)
Thank you

Hi,
Try this in you pre-query trigger.
-- if you want to add to the where clause do this
-- first store the current where clause
C_WHERE := get_block_property('your_block', default_where);
IF <condition> THEN
c_where := 'desired_condition'||' AND '||C_where;
-- append your condition to the existing one.
END IF;
set_block_property('your_block', default_where,c_where);
or if you want to totally replace it just use the set_block_property in the trigger.
Hope this helps.
Bob

SQL query optimization by changinf the WHERE clause

Hi all,
I need to know about the SQL query performance improvement by changing the WHERE clause. Consider a query :
select * from student where country ='India' and age = 20
Say, country = 'India' filters 100000 records and age = 20 filters 2000 records if given one by one. Now can anyone tell if the performance of the query can be changed by changing the query like this :
select * from student where age = 20 and country ='India'
as first where clause will give 2000 results and next filter will be applicable on only 2000 rows. While in the former query first where clause would give 100000 rows and seconde filter, hence, would be applicable on 100000 rows???
Kindly explain.
Thanks in advance.
Abhideep

in general the order of the where condition should not be important. However there are a few exeptions where sometimes it might play a role. Sometimes this is called order of filter conditions. Among others it depends on RBO or CBO used, Oracle Version, Indexes on the columns, statistic information on the table and the columns, CPU statistics in place etc.
If you want to make this query fast and you know that the age column has much better selectivity then you can simply put an index on the age column. An index on the country column is probably not useful at all, since to little different values are in this column. If you are already in 11g I would suggest to use a composite index on both columns with the more selective in first position.
Edited by: Sven W. on Nov 17, 2008 2:23 PM
Edited by: Sven W. on Nov 17, 2008 2:24 PM

Change block where clause !!

hello !!
i wanna change the where clause of the data block in the runtime !!
i know that it can by Set_block_property
but it don't work with me !!!
can u give me an example for that !!
and what is the differance between default_where and onetime_where ,,, a two attributes in the set_block_property !!

and what is the differance between default_where and onetime_where ,,, a two attributes in the set_block_property !!Default_where remains with the block for every query until you change it using pl/sql. The onetime_where is set null automatically immediately after a single query is executed.
Look up the on-line help for Set_Block_Property on default_where and onetime_where, then click the onetime_where link, and read that.

How to change recordset bahaviour to accept dynamic column names in the where clause

Hi
im using php-mysql and i make a recordset and i want to make the column names in the where clause to be dynamic like
"select id,name from mytable where $tablename-$myvar";
but when i do this my i break the recordset and it disappear
and when i use variables from advanced recordset it only dynamic for the value of the column not for the column name
and when i write the column name to dynamic as above by hand it truns a red exclamation mark on the server behaviour panel
so i think the only way is to change the recordset behaviour is it? if so How to make it accept dynamic column names?
thanks in advance.

As bregent has already explained to you, customizing the recordset code will result in Dreamweaver no longer recognizing the server behavior. This isn't a problem, but it does mean that you need to lay out your dynamic text with the Bindings panel before making any changes. Once you have changed the recordset code, the Bindings panel will no longer recognize the recordset fields.
Using a variable to choose a column name is quite simple, but you need to take some security measures to ensure that the value passed through the query string isn't attempting SQL injection. An effective way of doing this is to create an array of acceptable column names, and check that the value matches.
// create array of acceptable values
$valid = array('column_name1', 'column_name2', 'column_name3');
// if the query string contains an acceptable column name, use it
if (isset($_GET['colname']) && in_array($_GET['colname'], $valid)) {
$col = $GET['colname'];
} else {
// set a default value if the submitted one was invalid
$col = 'column_name1'
You can then use $col directly in the SQL query.

Performance with dates in the where clause

Performance with dates in the where clause
CREATE TABLE TEST_DATA
FNUMBER NUMBER,
FSTRING VARCHAR2(4000 BYTE),
FDATE DATE
create index t_indx on test_data(fdata);
query 1: select count(*) from TEST_DATA where trunc(fdate) = trunc(sysdate);
query 2: select count(*) from TEST_DATA where fdate between trunc(sysdate) and trunc(SYSDATE) + .99999;
query 3: select count(*) from TEST_DATA where fdate between to_date('21-APR-10', 'dd-MON-yy') and to_date('21-APR-10 23:59:59', 'DD-MON-YY hh24:mi:ss');
My questions:
1) Why isn't the index t_indx used in Execution plan 1?
2) From the execution plan, I see that query 2 & 3 is better than query 1. I do not see any difference between execution plan 2 & 3. Which one is better?
3) I read somewhere - "Always check the Access Predicates and Filter Predicates of Explain Plan carefully to determine which columns are contributing to a Range Scan and which columns are merely filtering the returned rows. Be sceptical if the same clause is shown in both."
Is that true for Execution plan 2 & 3?
3) Could some one explain what the filter & access predicate mean here?
Thanks in advance.
Execution Plan 1:
SQL> select count(*) from TEST_DATA where trunc(fdate) = trunc(sysdate);
COUNT(*)
283
Execution Plan
Plan hash value: 1486387033
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 1 | 9 | 517 (20)| 00:00:07 |
| 1 | SORT AGGREGATE | | 1 | 9 | | |
|* 2 | TABLE ACCESS FULL| TEST_DATA | 341 | 3069 | 517 (20)| 00:00:07 |
Predicate Information (identified by operation id):
2 - filter(TRUNC(INTERNAL_FUNCTION("FDATE"))=TRUNC(SYSDATE@!))
Note
- dynamic sampling used for this statement
Statistics
4 recursive calls
0 db block gets
1610 consistent gets
0 physical reads
0 redo size
412 bytes sent via SQL*Net to client
380 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
Execution Plan 2:
SQL> select count(*) from TEST_DATA where fdate between trunc(sysdate) and trunc(SYSDATE) + .99999;
COUNT(*)
283
Execution Plan
Plan hash value: 1687886199
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 1 | 9 | 3 (0)| 00:00:01 |
| 1 | SORT AGGREGATE | | 1 | 9 | | |
|* 2 | FILTER | | | | | |
|* 3 | INDEX RANGE SCAN| T_INDX | 283 | 2547 | 3 (0)| 00:00:01 |
Predicate Information (identified by operation id):
2 - filter(TRUNC(SYSDATE@!)<=TRUNC(SYSDATE@!)+.9999884259259259259259
259259259259259259)
3 - access("FDATE">=TRUNC(SYSDATE@!) AND
"FDATE"<=TRUNC(SYSDATE@!)+.999988425925925925925925925925925925925
9)
Note
- dynamic sampling used for this statement
Statistics
7 recursive calls
0 db block gets
76 consistent gets
0 physical reads
0 redo size
412 bytes sent via SQL*Net to client
380 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows
Execution Plan 3:
SQL> select count(*) from TEST_DATA where fdate between to_date('21-APR-10', 'dd-MON-yy') and to_dat
e('21-APR-10 23:59:59', 'DD-MON-YY hh24:mi:ss');
COUNT(*)
283
Execution Plan
Plan hash value: 1687886199
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 1 | 9 | 3 (0)| 00:00:01 |
| 1 | SORT AGGREGATE | | 1 | 9 | | |
|* 2 | FILTER | | | | | |
|* 3 | INDEX RANGE SCAN| T_INDX | 283 | 2547 | 3 (0)| 00:00:01 |
Predicate Information (identified by operation id):
2 - filter(TO_DATE('21-APR-10','dd-MON-yy')<=TO_DATE('21-APR-10
23:59:59','DD-MON-YY hh24:mi:ss'))
3 - access("FDATE">=TO_DATE('21-APR-10','dd-MON-yy') AND
"FDATE"<=TO_DATE('21-APR-10 23:59:59','DD-MON-YY hh24:mi:ss'))
Note
- dynamic sampling used for this statement
Statistics
7 recursive calls
0 db block gets
76 consistent gets
0 physical reads
0 redo size
412 bytes sent via SQL*Net to client
380 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed

Hi,
user10541890 wrote:
Performance with dates in the where clause
CREATE TABLE TEST_DATA
FNUMBER NUMBER,
FSTRING VARCHAR2(4000 BYTE),
FDATE DATE
create index t_indx on test_data(fdata);Did you mean fdat<b>e</b> (ending in e)?
Be careful; post the code you're actually running.
query 1: select count(*) from TEST_DATA where trunc(fdate) = trunc(sysdate);
query 2: select count(*) from TEST_DATA where fdate between trunc(sysdate) and trunc(SYSDATE) + .99999;
query 3: select count(*) from TEST_DATA where fdate between to_date('21-APR-10', 'dd-MON-yy') and to_date('21-APR-10 23:59:59', 'DD-MON-YY hh24:mi:ss');
My questions:
1) Why isn't the index t_indx used in Execution plan 1?To use an index, the indexed column must stand alone as one of the operands. If you had a function-based index on TRUNC (fdate), then it might be used in Query 1, because the left operand of = is TRUNC (fdate).
2) From the execution plan, I see that query 2 & 3 is better than query 1. I do not see any difference between execution plan 2 & 3. Which one is better?That depends on what you mean by "better".
If "better" means faster, you've already shown that one is about as good as the other.
Queries 2 and 3 are doing different things. Assuming the table stays the same, Query 2 may give different results every day, but the results of Query 3 will never change.
For clarity, I prefer:
WHERE fdate >= TRUNC (SYSDATE)
AND fdate < TRUNC (SYSDATE) + 1(or replace SYSDATE with a TO_DATE expression, depending on the requirements).
3) I read somewhere - "Always check the Access Predicates and Filter Predicates of Explain Plan carefully to determine which columns are contributing to a Range Scan and which columns are merely filtering the returned rows. Be sceptical if the same clause is shown in both."
Is that true for Execution plan 2 & 3?
3) Could some one explain what the filter & access predicate mean here?Sorry, I can't.

How do I modify the WHERE clause in my SQL query?

This seems like such a straight-forward part of the report design, but I'm fairly new to Crystal Reports and I only have experience with modifying reports someone else has already written. In this particular case, I just need to modify the WHERE clause of the SQL query. I can select Show SQL Query and see what statement is being used to select data, but I can't find where to modify it since it's grayed out. I see how to change the selection criteria, parameters, grouping, etc...just not the WHERE clause. The report is linked to a database used for reporting with a table created and populated by a stored procedure. I don't need to modify the stored procedure because the data I want to filter by is currently in the table--I just don't know how to filter by what I need. Here's part of the query:
SELECT "rpt_dist"."startdate", "rpt_dist"."transtype", "rpt_dist"."laborcode", "rpt_dist"."crewid", "rpt_dist"."regularhrs" FROM "Reporting"."dbo"."rpt_dist" "rpt_dist"
WHERE (rpt_dist."transtype" <> 'WORK' AND rpt_dist."transtype" <> 'WMATL') AND rpt_dist."laborcode" LIKE 'S%' AND (rpt_dist."crewid" = 'HOUS' OR rpt_dist."crewid" = 'HOUS2' ...
I would like to add another crewid to the WHERE clause. Thanks for any input.

1.Open the report in the crystal designer
2.Go to the field explorer(if hidden go to view menu->field explorer)
3.Rt. click on the database fields->choose database expert
4.Now you will see 2 columns-Available DataSource and Selected Tables
5.Rt. click on the object(ex.command) available in the Selected Tables column->Choose Edit command
6.A new Modify Command window will appear,here you can edit your SQL Query
I get to step 4 and I see the two columns including my database and the report table, but there is no command object available. If I right-click on my table, I can just view the Properties. ??
As for the other tip to modify the record selection: I don't see anywhere the other crewid values are set and if I add the one I'm missing, it doesn't modify the existing SQL Query and when I preview the report it throws off the results so that no data displays??
I'm using Crystal Reports 11.5 if that makes a difference. Thanks again.

Case or Decode in the Where clause

Dear all,
My requirement is:
If user select other then "ALL"option from the LOV the following condition should be part of the where clause.
current_req_status = :block1.req_statusIf user select "ALL" from the lov no need to append the above condition in the where clause.
Please give me the sample code
select request_id,doc_name,doc_code,part_id,current_req_status from test_table
where req_type = 'I'
and doc_code = :BLOCK1.doc_code
and -- Here is the condition is changed based on
        the :BLOCK1.req_status(LOV).
     -- If user select other then "All" option from
        this LOV the query append the below condition
        current_req_status = :block1.req_status
      -- Else no need append the above condition
         in the query where clause.Edited by: roots on Apr 10, 2012 9:31 AM
Edited by: roots on Apr 10, 2012 9:38 AM

Hi InoL,
In the database column not having "ALL" value inside. so the match does not return any values.
My LOV has "A1,A2,A3,A4,....ALL" . the database column having "A1,A2,A3,A4.......". here no "ALL" value.
So if user select "ALL" option from this LOV, that means select all vaules from the database (A1,A2,A3,A4......)..
If user select A1 from the lov the select query include only the matched
column values.from example,
select....
where nvl(database_column,'X')= nvl(:Block1.LOV_value)If user select "ALL" option then no need for above condition in the where clause so that query returns all the rows from the database column.
hope I've clearly explain my requirement.
Thanks lot,
Roots.

Subquery in the Where clause

Can I put a subquery in the where clause, on the left side on the operator?
This is a multi-row query.
Like this,
   select a.col1, a.col2, b.col1, b.col2,
             my_function(a.date1, b.date2) AS GROSSDAYS
   from table1 a
   where ( select ( a.date1 - b.date2 ) as range
               from     table1 a
               join      table2 b
               on       a.col3 = b.col3
               where rownum =1
               in ( 1,2,3)
and a.col1 = b.col2I need to use a subquery because the column I need does not exist in the table, and I cannot make any changed to the table structure.
Is what I'm doing possible?
The subquery is the same as the function I have in the Select clause.

I tried a subquery in the where clause, but now I'm getting a missing expression error!
   SELECT
        r.complete_flag, r.order_num, r.referral_num, TRUNC(r.referral_datetime) AS referral_datetime,
        r.clinic_specialty, a.appointment_datetime, TRUNC(a.appointment_date_made) AS appt_datemade, a.appointment_status_id,
         scref.scr_rules.calcatcdays(r.referral_datetime,a.appointment_date_made) AS ATCDays -- returns difference between two dates
FROM
        referral r,
                             ( SELECT referral_num,appointment_datetime, appointment_date_made, appointment_status_id
                                  FROM   ( SELECT referral_num, appointment_datetime, appointment_date_made, appointment_status_id,
                                            ROW_NUMBER() OVER (PARTITION BY referral_num
                                            ORDER BY appointment_datetime) rn
                                        FROM   appointment
                                 WHERE rn = 1
                         a
WHERE r.order_num IS NOT NULL
AND   ( SELECT adays                      -- THIS IS WHERE I'M GETTING A MISSING EXPRESSION ERROR!!!
       FROM ( SELECT scref.scr_rules.calcatcdays(r.referral_datetime,a.appointment_date_made) AS adays
                FROM referral r
                 JOIN appointment a
                 ON   a.referral_num = r.referral_num
                 WHERE ROWNUM = 1
       WHERE adays
      ) = 3
AND   r.referral_num = a.referral_num(+)
AND   TRUNC(r.referral_datetime) >= TO_DATE('01-JUL-05','DD-MON-YY')
AND   TRUNC(r.referral_datetime) <= TO_DATE('31-JUL-05','DD-MON-YY')

Time's error with a metric for DashBoard in the WHERE Clause - @Prompt

Hello,
I have a problem with a measure in Universe. In the WHERE clause I have the typical @Prompt to interact with DashBoard:
"Fact.Time_Key between @Prompt('BEGIN_DATE','D',,mono,free) And @Prompt('END_DATE','D',,mono,free)" *
*Fact.Time_Key is a Date Field
I check many options to solve the problem, which is: "The conversion of char data type to smalldatetime data type result in an out-of-range smalldatetime value." For example I saw many forums, I check the regional settings with IT and I also change the prm file that my universe's connection use but it still doesn't work.
So I believe that the date format of my field (Fact.Time_Key) is different to @Prompt date format
Any Suggestion?
Regards
Romá

Hi Roman,
I am not sure but I thought there was also a 'BEGIN_DATETIME' option
Regards
Alan

Parsing an input parameter for the where clause or record select value

In my limited CR experience, I've always used a command database connection so that I can write my own SQL. However, now I have to parse a pipe delimited parameter to get my value for the where clause, so I'm selecting several tables and joining them through the Database Expert Links tab. All works fine, but after doing that and then parsing the parameter with the below formula in the Select Expert, I notice that there is no where clause in the SQL query, and although the report eventually displays the proper values, it runs through thousands of records first. Here is my Select Expert - Record formula:
StringVar array Parm1;
Parm1 := Split({?DATA_AREA}, "|");
{SO_ORDERS.CASE_ID} = Parm1[2]
If I change "Parm1[2]" on the last line to a valid Case ID, then there is a where clause in the SQL and the report generates immediately.
It seems like the record select formula is applied AFTER all of the records (without a where clause) are searched when I use the parsed parameter value, but when I hard code a valid value, it places that into the where clause BEFORE the sql is executed. Is there a way to get the parameter parsed first and then use that parsed value in the SQL where clause?
Thanks.
Bill

Yes crystal will run the query first to get 100% data and then applies record selection condition. To increase the performance you need to pass the where condition at the command level instead of report level. So you need to create a report using add command like this
select * from tablename where field={?Parameter}
{?Parameter} is a command level parameter.
Now insert this report as a subreport in another report which has no connection but has a parameter
{?DATA_AREA} and create a formula like this in the main report
Split({?DATA_AREA}, "|")[2]
Now right click on the subreport and go to change subreport links and add this formula from main report and link this to sub report parameter {?Parameter} without linking any database field from the subreport.
Now your subreport runs with the where clause to get the data.
Regards,
Raghavendra

JSP, DataWebBean: How to dynamically set the where clause of query and display record

Hi,
I am reposting this question as per suggestions made by Mr. Dwight.
I have used ViewCurrentRecord web bean to display records from EMP table. I have to use the Dept_Id_FK from the current
record of the EMP table to display corresponding records of Dept table. I have a view object called DeptView in my Business
Components which selects all the records from the Dept table.
How do I get the value of Dept_Id_FK and use it to display the required records of the Dept table?
I tried to declare a variable and get the value of Dept_Id_FK but it did not work. My code is as follows:
<%! String m_DeptId = null; %>
<jsp:useBean id="RowViewer" class="oracle.jbo.html.databeans.ViewCurrentRecord" scope="request">
<%
RowViewer.initialize(pageContext, "EMPApp_EMP_EMPAppModule.EMPView1");
RowViewer.setReleaseApplicationResources(false);
RowViewer.getRowSet().next();
m_DeptId = (String)RowViewer.getRowSet().getCurrentRow().getAttribute("DeptIdFk");
%>
</jsp:useBean>
Thanks.
null

First of all, Thank you very much for making use of the new topic format. It is very much appreciated.
As for your question, I think there are several different ways to accomplish what I think you want to do.
1. Create a view object that includes both Emp and Dept entities and join them there. In this case, your query would look something like this:
Select e.empno,e.name,...,d.dname,d.loc from emp e, dept d
where e.deptno = d.deptno
You should be able to create a JSP off of this view object that contains both the employee and department information. In this case, BC4J takes care of the foreign key to primary key coordination.
2. In order to set a dynamic where clause for a view, you need to do the following in your usebean tag:
rsn.initialize(application,session, request,response,out,"DeptView");
rsn.getRowSet().getViewObject().setWhereClause("deptno=" | | m_DeptId);
rsn.getRowSet().getViewObject().executeQuery();
rsn.getRowSet().first();
You will need to do this in a separate usebean tag from the EmpView, since the usebean can only initialize one view object.
In other words, you would have your ViewCurrentRecord bean tag for the EmpView, then a separate one for the DeptView where you use the above code to set the where clause to display just the information for the department you want.
Another option, but one I'm not sure would work as well, is to create a master-detail JSP to do this for you. Usually a master-detail is a one-to-many (one department to many employees). Your request appears to be the reverse, but might still be doable using the same mechanism.
You set up relationships between views in your BC4J project using View Links. If you used the BC4J project wizard and created default views, some of these links may have been created for you. They are created when BC4J detects a foreign key to primary key relationship in the database.
You can create your own View Links using the View Link wizard. Select your BC4J project node and choose Create View Link... from the context menu. You will be asked to select a source view (Emp), and a target view (Dept), then select the attribute in each view that related the two of them (deptno).
Next, you need to reflect this new relationship setting in your application module. Select your app module and choose Edit from the context menu. On the data model page, select the EmpView node in the Selected list. Now select the DeptView node in the available list and shuttle it over. You should see DeptView1 via yourlink appear indented under the EmpView node. Save and rebuild your BC4J project to reflect the changes.
In your JSP project, you can now have the wizard create a master-detail form for you based on DeptView1.
Let me know if the above answers your question, or if I have misunderstood what it is you wanted to do.
null

Function-based index with OR in the wher-clause

We have some problems with functin-based indexes and
the or-condition in a where-clause.
--We use Oracle 8i (8.1.7)
create table TPERSON(ID number(10),NAME varchar2(20),...);
create index I_NORMAL_TPERSON_NAME on TPERSON(NAME);
create index I_FUNCTION_TPERSON_NAME on TPERSON(UPPER(NAME));
The following two statements run very fast on a large table
and the execution-plan asure the usage of the indexes
(-while the session is appropriate configured and the table is analyzed):
1)     select count(ID) FROM TPERSON where upper(NAME) like 'MIL%';
2)     select count(ID) from TPERSON where NAME like 'Mil%' or (3=5);
In particular we see that a normal index is used while the where-clause contains
an OR-CONDITION.
But if we try the similarly select-statement
3)     select count(ID) FROM TPERSON where upper(NAME) like 'MIL%' or (3=5);
the CBO will not use the function-index I_FUNCTION_TPERSON_NAME and we have a full table scan in the execution-plan.
(This behavior we only expect with views but not with indexes.)
We ask for an advice like a hint, which enable the CBO-usage
of function-based indexes in connection with OR.
This problem seems to be artificial because it contains this dummy logic:
     or (3=5).
This steams from an prepared statement, where this kind of boolean
flag reduce the amount of different select-statements needed for
covering the hole business-logic, while using bind-variables for the
concrete query-parameters.
A more realistic (still boild down) version of our select-statement is:
select * FROM TPERSON
where (upper(NAME) like 'MIL%' or (NAME is null))
and (upper(FIRSTNAME) like 'MICH% or (FIRSTNAME is null))
and ...;
thank you for time..
email: [email protected]

In the realistic statement you write :
select * FROM TPERSON
where (upper(NAME) like 'MIL%' or (NAME is null))
and (upper(FIRSTNAME) like 'MICH% or (FIRSTNAME is null))
and ...;
as far as i know, NULL values are not indexed, "or (NAME is NULL)" have to generate a full table scan.
HTH
We have some problems with functin-based indexes and
the or-condition in a where-clause.
--We use Oracle 8i (8.1.7)
create table TPERSON(ID number(10),NAME varchar2(20),...);
create index I_NORMAL_TPERSON_NAME on TPERSON(NAME);
create index I_FUNCTION_TPERSON_NAME on TPERSON(UPPER(NAME));
The following two statements run very fast on a large table
and the execution-plan asure the usage of the indexes
(-while the session is appropriate configured and the table is analyzed):
1)     select count(ID) FROM TPERSON where upper(NAME) like 'MIL%';
2)     select count(ID) from TPERSON where NAME like 'Mil%' or (3=5);
In particular we see that a normal index is used while the where-clause contains
an OR-CONDITION.
But if we try the similarly select-statement
3)     select count(ID) FROM TPERSON where upper(NAME) like 'MIL%' or (3=5);
the CBO will not use the function-index I_FUNCTION_TPERSON_NAME and we have a full table scan in the execution-plan.
(This behavior we only expect with views but not with indexes.)
We ask for an advice like a hint, which enable the CBO-usage
of function-based indexes in connection with OR.
This problem seems to be artificial because it contains this dummy logic:
     or (3=5).
This steams from an prepared statement, where this kind of boolean
flag reduce the amount of different select-statements needed for
covering the hole business-logic, while using bind-variables for the
concrete query-parameters.
A more realistic (still boild down) version of our select-statement is:
select * FROM TPERSON
where (upper(NAME) like 'MIL%' or (NAME is null))
and (upper(FIRSTNAME) like 'MICH% or (FIRSTNAME is null))
and ...;
thank you for time..
email: [email protected]

Using if logic in the where clause of a select statement

I have a select clause. And in the select clause there is a variable all_off_trt that can be 'Y' or 'N'.
In the where clause I want to make it so that if a form variable is checked and all_off_trt is 'Y' then
exclude it else if the form variable isn't checked then select it no matter what all_off_trt is.
Is there any way to include either and if statement or a case statement within the where clause to acheive this? If not is there another way of doing it?
Basically I am looking for a case statement like this
case
when all_off_trt = 'Y' and mail_para.code = 'Y' then false
else true
end
Message was edited by:
Tugnutt7

Ok, so that really doesn't solve my problem. I have 3 different fields that I need to do that with. Each combining in a select statement to print an email list, as well as other thing limiting the where clause.
This is currently what I have, tested and working 100%.
cursor email_cur is
select unique p.email,s.all_off_trt,s.all_deceased,s.no_enroll
from participant p, trialcom t, ethics s
where p.status='A'
and p.surname=t.surname
and p.initials=t.initials
and s.trial_cd = t.tricom
and s.centre = t.centre
and p.email is not null
and (t.centre in (select code from mail_parameters where user_name=user and mail_para='CENTRE')
or 'XX' in (select code from mail_parameters where user_name=user and mail_para='CENTRE'))
and (t.tricom in (select code from mail_parameters where user_name=user and mail_para='TRIAL')
or 'XX' in (select code from mail_parameters where user_name=user and mail_para='TRIAL'))
and (t.role in (select code from mail_parameters where user_name=user and mail_para='ROLE')
or 'XX' in (select code from mail_parameters where user_name=user and mail_para='ROLE'))
and (p.country in (select code from mail_parameters where user_name=user and mail_para='COUNTRY')
or 'XX' in (select code from mail_parameters where user_name=user and mail_para='COUNTRY'))
and (t.represent in (select code from mail_parameters where user_name=user and mail_para='REPRESENT')
or 'XX' in (select code from mail_parameters where user_name=user and mail_para='REPRESENT'));
This is in a program unit that runs when a button is clicked. At the end of that I need to add on the 3 case statements that help further narrow down the selection of emails to be printed. Then it prints the emails selected from this statement into a file. So it has to be done right in the select statement. The three table variables are the all_off_trt, all_deceased, and no_enroll. The form has 3 checkboxes. One for each, that when checked (giving the variable associated with the checkboxes a value of 'Y') excludes all emails that have a 'Y' in the coresponding table variable.

Chang the WHERE clause

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