In my Oracle APEX application page I have checkbox item with multiple values. The source of checkbox is like this:
STATIC:One,Two,Apple
In page process I need to use the value from checkbox in PL/SQL code. As far as I understand I get colon separated values. Question is how to use those values and test if Value is One, then do this. If Two is checked as well, then do something more.
Depending on situation you can use:
Convert string with delimiter to table (you can use this as subquery):
select regexp_substr('1:2:3','[^:]+', 1, level) ID from dual
connect by regexp_substr('1:2:3', '[^:]+', 1, level) is not null;
ID
--
1
2
3
Check one value using instr:
where instr('1:2:3', '2') > 0
If value of the second argument of the function is contained inside the first argument - function returns its position, otherwise - 0.
For performance I prefer the INSTR function, e.g. INSTR(':'||:p_item||':',':Two:') > 0
Related
I'm trying to get the area of explicitly written polygon without any success.
SELECT SDO.GEOM.SDO_AREA('POLYGON ((...))')
... contains my polygon values
I'm getting error:
SQL Error [923] [42000]: ORA-00923: FROM keyword not found where expected
How can I write my polygon in the select query and get the area of this polygon ?
It is SDO_GEOM.SDO_AREA and not SDO.GEOM.SDO_AREA.
You need to pass a SDO_GEOMETRY object as the first argument and not a string (containing a GIS shape).
You need a second argument containing the tolerance (or a SDO_DIM_ARRAY).
You need a FROM clause and a table to select from (DUAL is usually used if you only want a single row).
You need to pass a valid GIS shape; ... is not valid.
Like this:
SELECT SDO_GEOM.SDO_AREA(
SDO_GEOMETRY('POLYGON ((0 0, 0 1, 1 1, 1 0))'),
0.0000000005
)
FROM DUAL;
db<>fiddle here
This might be a silly one but haven't been able to figure it out.
I have a Checkbox Group Item (with Static info) with 4 different options, I want to limit the amount of checked boxes to just two. Is this something possible to make?
Thank you
A checkbox is submitted as a colon-separated string. APEX_STRING has lots of functionality to convert the string to a pl/sql collection (and back). Once converted you can use functions like FIRST, LAST, COUNT. Or even compare collections using INTERSECT. For checking a max nr, a COUNT is enough.
So the validation would be something like this (type Function Body returning Error Text):
DECLARE
l_arr apex_t_varchar2;
BEGIN
l_arr := apex_string.split(:P13_CHECKBOX,':');
IF l_arr.COUNT > 2 THEN
RETURN 'Can only select 2 values';
ELSE
RETURN NULL;
END IF;
END;
this is my first post here, I'd like to ask for help on a theoretically simple query.
The current query I'm creating is to try and generate a random number, which will be identified as even or odd. Depending on that value, it should print either "M" as even, or "W" as odd. Though when I try using a case inside the select, I'm getting the "missing keyword" error. This is my following code:
select
case
when mod(round(dbms_random.value(1,100)),2) = 0 then dbms_output.put_line('M');
when mod(round(dbms_random.value(1,100)),2) = 1 then dbms_output.put_line('W');
end
from dual
I've tried checking the website for similar problems, and while I've found similar problems and people getting the solution correctly, I don't quite know what I'm missing here. When I run the select alone, I get the even or odd number I want to get, but not when I try to print out a result.
SELECT statement cannot PRINT, it can only RETURN something.
You may use query like
select
v,
case when mod(v, 2) = 0 then 'M' else 'W' end l
from
(select round(dbms_random.value(1, 100)) v from dual)
and process it's result as you wish (print, for example).
Why are you trying to embed dbms_output in a query? Just write:
select
case
when mod(round(dbms_random.value(1,100)),2) = 0 then 'M'
when mod(round(dbms_random.value(1,100)),2) = 1 then 'W'
end
from dual
Also you know, since you are calling dbms_random two different times, you get two different values in the same query. If you want one value to be compared, then use a WITH clause
with rand_value as
( select round(dbms_random.value(1,100)) val from dual
)
select
case
when mod(val,2) = 0 then 'M'
when mod(val,2) = 1 then 'W'
end
from rand_value
You get the error because of the semicolons.
Also you are calling the random function twice and thus get two different random values. I would use IF-THEN-ELSE instead of a SELECT statement, since the latter one cannot print.
IF mod(round(dbms_random.value(1,100)),2) = 0 THEN
dbms_output.put_line('M');
ELSE
dbms_output.put_line('W');
END IF;
I have an SSRS report where there is a parameter that asks the user to include records where revenue is greater than zero, or records with revenue values that are just zero.
Since the query is not a stored procedure and it is not an option to put it into a procedure, I need to use some case logic for the embedded query. I need to do this in the where clause in the end.
I am trying to do something like this:
SELECT * FROM TABLE
WHERE MY_DATE BETWEEN D_START AND D_END
AND
CASE
WHEN :REVENUE = 1 THEN REV != 0
WHEN :REVENUE = 2 THEN REV = 0
END
However, when I run this query I get the following error:
ORA-00905: missing keyword
Is what I am doing not possible? Or is there an error that someone can see and help me with?
Please help. Thanks!
UPDATE: Just to clarify, the user is passing a value of 1 or 2. And the query should filter the data according to what value is passed to it. If 1 is passed in the parameter, then filter out all revenue not equal to zero. Else if two is passed, then filter so that only records where revenue is zero is returned.
You can write it better with a bit of boolean logic:
SELECT * FROM TABLE
WHERE MY_DATE BETWEEN D_START AND D_END
AND (
(:REVENUE = 1 AND REV != 0)
OR
(:REVENUE = 2 AND REV = 0 )
)
CASE is meant to extract different values based on conditions, so you can use it to check conditions, but you need to use it as a value to check against a condition
It's not necessary to use a CASE expression to get this particular result.
But it is possible to make use of one.
The problem in the original query is that Oracle is more strict than other databases (like MySQL) in that Oracle doesn't implicitly convert a boolean expression to a value, or convert a value into boolean.
I suspect that Oracle is choking in a couple of places. The error message is only showing us one of those.
The CASE expression returns a value, and Oracle is balking that he won't evaluate the value as a boolean.
To get that value evaluated as a boolean, we could do a comparison of the value to some other value.
If we fix that, I think Oracle is still going to choke on the expression following THEN. Oracle is expecting to return a value, and it's finding a comparison, which evaluates to a boolean.
Okay, so we know the CASE expression needs to return a value, and we need to use that in a boolean expression. If we move that conditional test into the WHEN part, and specify a value to be returned in the THEN, we can compare the return from the CASE expression to another value.
(As an aside... I strongly recommend that you qualify the column references in the SQL statement. That makes the intent more clear. Looking at the statement, it looks like MY_DATE, D_START and D_END are all column references. That's perfectly valid, it just seems a bit odd to me.)
As an example, we could do something like this with the CASE expression:
SELECT t.*
FROM TABLE t
WHERE t.MY_DATE BETWEEN t.D_START AND t.D_END
AND CASE
WHEN ( :REVENUE = 1 AND t.REV != 0 ) THEN 1
WHEN ( :REVENUE = 2 AND t.REV = 0 ) THEN 1
ELSE NULL
END = 1
The parens inside the CASE aren't necessary; I just included them to highlight the part that Oracle is evaluating in a boolean context.
So, does that work? If the value passed in for :REVENUE is 2, the condition in the first WHEN won't evaluate to TRUE (the result of first comparison is guaranteed to be FALSE). The condition in the second WHEN may evaluate to TRUE (first comparison will yield TRUE, the result from second comparison will depend on the value in the REV column.)
That CASE expression is either going to return a value of 1 or NULL. (We could just as easily use a 0 or a -1, or 999 in place of NULL if we wanted.)
Once the CASE expression is evaluated, the value returned will be compared to a literal value, as if we wrote e.g. val = 1. That comparison is evaluated as boolean. If it evaluates to TRUE, the row will be returned...
To get Oracle to behave similarly to other databases (like MySQL), we would need to make the conversion from boolean to value and value to boolean explicit. We would still need the return from the CASE compared to 1, like we did above. In place of REV != 0 we could use another CASE expression. I'm not recommending this, just shown here for illustration, converting a boolean to a value.
WHERE CASE
WHEN ( :REVENUE = 1 )
THEN CASE WHEN ( t.REV != 0 ) THEN 1 ELSE NULL END
WHEN ( :REVENUE = 2 )
THEN CASE WHEN ( t.REV = 0 ) THEN 1 ELSE NULL END
ELSE
NULL
END = 1
Note that the return from the outermost CASE expression is being compared to a value, so we get a boolean (where Oracle expects a boolean.)
All of the ELSE NULL in the statements above can be omitted for an equivalent result, since that's the default when ELSE is omitted.)
Again, it's not necessary to use a CASE expression. You can get equivalent results without it. For example:
SELECT t.*
FROM TABLE t
WHERE t.MY_DATE BETWEEN t.D_START AND t.D_END
AND ( ( :REVENUE = 1 AND t.REV != 0 )
OR ( :REVENUE = 2 AND t.REV = 0 )
)
In these queries that all return an equivalent result, the CASE expression doesn't buy us anything. But in some circumstances, it can have some advantages over a regular OR, because the CASE expression stops evaluation when a condition in a WHEN clause evaluates to TRUE.
The problem is that Oracle SQL does not have the boolean data type, so you cannot have columns of type boolean, pass boolean parameters to a query, have boolean expressions etc. So they have the somewhat unnatural concept of "condition" which is something that goes into logical conditions (like in the WHERE clause). Unfortunately, when they introduced the case EXPRESSION, which can be used wherever any other expression can be used (but this excludes boolean), they DID NOT introduce a "case CONDITION" - which could be used where other conditions can be used. This omission is odd, since the code for a case condition would probably use 95% of the code for the case expression. All the more weird since PL/SQL does have the boolean type, and the case expression there works seamlessly for Booleans.
Crystal 2008. Have record selection formula ending with
and
( ( "Zero" in {?Credit_Debit} and {V_ARHB_BKT_AGING_DETAIL.AMOUNT} = 0)
or ( "Credit" in {?Credit_Debit} and {V_ARHB_BKT_AGING_DETAIL.AMOUNT} < 0)
or ( "Debit" in {?Credit_Debit} and {V_ARHB_BKT_AGING_DETAIL.AMOUNT} > 0) )
but no matter what combination of values is selected for Credit_Debit the result set is the same.
Also without success, I tried joining the parameter array into a single string and using lines like
or ( {#Cred_Deb_Choices} like "*Credit*" and {V_ARHB_BKT_AGING_DETAIL.AMOUNT} < 0)
Using the first method works in the same formula when the parameter values are integers, as:
and ({?Location ID} = 0 or {V_ARHB_BKT_AGING_DETAIL.LOC_ID} in {?Location ID})
I examined the generated SQL, and saw that the part at the beginning that had no effect was not shown.
I changed a part that tested for a hard-coded value to instead test for a parameter value, and looked at the SQL again. No change.
When you try to create a filter that doesn't fit with the datatype of the field then that doesn't get reflected in record selection formula.
For Integer field give integers in record selection for text give text.
E.g:
ID=0 and Name='XXX' works
ID='Zero' and Name='XXX' doesn't
This should solve your issue