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I have a table, inside there is a field called x, the x field contain value of '1+2', '1+3' etc, how to get these value and calculate it and save into another field?
For simple arithmetic expressions - and depending on your Oracle version - you could use xmlquery to evaluate. Note that / has special meaning in xml, the operator for division is the keyword div - so you need a replace in case you may have forward slashes in the arithmetic expression. (If you don't have any divisions, you can simplify the query by removing the call to replace.)
Here is an example - including the test data at the top, in a with clause (not part of the solution!)
with
test_data (str) as (
select '1 + 3' from dual union all
select '3 * 5 - 2' from dual union all
select '2/4*6' from dual union all
select '3 * (1 - 3)' from dual
)
select str, xmlquery(replace(str, '/', ' div ') returning content).getNumberVal()
as evaluated_expression
from test_data;
STR EVALUATED_EXPRESSION
----------- --------------------
1 + 3 4
3 * 5 - 2 13
2/4*6 3
3 * (1 - 3) -6
If you only have valid PL/SQL arithmetic expressions in your formulas, then you can use EXECUTE IMMEDIATE to evaluate them.
For this, you'll need to create a function:
create or replace function eval_expression(p_expression in varchar2)
return number is
query varchar2(100);
result number;
begin
query := 'select ' || p_expression || ' from dual';
execute immediate query
into result;
return result;
end eval_expression;
Then you can use this function in UPDATE query:
update t
--val is another field
set t.val = eval_expression(t.x)
Naturally, with EXECUTE IMMEDIATE this query won't be extremely efficient, but it'll work. Also, with dynamic queries we're going into unsafe territory, so make sure that you don't have malicious code among your formulas.
Also, see "Evaluate Expression" on Ask TOM. Tom Kyte used a slightly more civilized approach (dbms_sql package) and created a package with a single variable support.
If the case you have mentioned needs to be considered then I will suggest you use the following query:
select
xmlquery('3+4'
returning content
).getNumberVal()
from
dual;
If More operators are involved except division then the aforementioned query will work but if the division operator is also involved then you must have to replace "/" with " div " keyword. Something like the following:
select
xmlquery(
replace( '20/5', '/', ' div ')
returning content
).getNumberVal()
from
dual;
Now, you can use it in your update statement or anywhere else.
update tab
set tab.result_column_name = xmlquery(t.your_expr_column_name
returning content
).getNumberVal()
update tab
set tab.result_column_name = xmlquery(
replace( t.your_expr_column_name, '/', ' div ')
returning content
).getNumberVal()
Demo
Cheers!!
I need help
i have records 123,456,789 in rows when i am execute like
this one is working
select * from table1 where num1 in('123','456')
but when i am execute
select * from table1 where num1 in(select value from table2)
no resultset found - why?
Check the DataType varchare2 or Number
try
select * from table1 where num1 in(select to_char(value) from table2)
Storing comma separated values could be the cause of problem.
You can try using regexp_substr to split comma.
First and foremost, an important thing to remember: Do not store numbers in character datatypes. Use NUMBER or INTEGER. Secondly, always prefer VARCHAR2 datatype over CHAR if you wish to store characters > 1.
You said in one of your comments that num1 column is of type char(4). The problem with CHAR datatype is that If your string is 3 characters wide, it stores the record by adding extra 1 space character to make it 4 characters. VARCHAR2 only stores as many characters as you pass while inserting/updating and are not blank padded.
To verify that you may run select length(any_char_col) from t;
Coming to your problem, the IN condition is never satisfied because what's actually being compared is
WHERE 'abc ' = 'abc' - Note the extra space in left side operator.
To fix this, one good option is to pad the right side expression with as many spaces as required to do the right comparison.The function RPAD( string1, padded_length [, pad_string] ) could be used for this purpose.So, your query should look something like this.
select * from table1 where num1 IN (select rpad(value,4) from table2);
This will likely utilise an index on the column num1 if it exists.
The other one is to use RTRIM on LHS, which is only useful if there's a function based index on RTRIM(num1)
select * from table1 where RTRIM(num1) in(select value from table2);
So, the takeaway from all these examples is always use NUMBER types to store numbers and prefer VARCHAR2 over CHAR for strings.
See Demo to fully understand what's happening.
EDIT : It seems You are storing comma separated numbers.You could do something like this.
SELECT *
FROM table1 t1
WHERE EXISTS (
SELECT 1
FROM table2 t2
WHERE ',' ||t2.value|| ',' LIKE '%,' || rtrim(t1.num1) || ',%'
);
See Demo2
Storing comma separated values are bound to cause problems, better change it.
Let me tell you first,
You have stored values in table2 which is comma seperated.
So, how could you match your data with table1 and table2.
Its not Possible.
That's why you did not get any values in result set.
I found the Solution using string array
SELECT T.* FROM TABLE1 T,
(SELECT TRIM(VALUE)AS VAL FROM TABLE2)TABLE2
WHERE
TRIM(NUM1) IN (SELECT COLUMN_VALUE FROM TABLE(FUNC_GETSTRING_ARRAY(TABLE2.VAL)))
thanks
I'm new to Oracle and recently ran into the following query. I'm trying to understand what it's doing and hopefully rewrite it to optimize it. In this example, :NameList would be a comma separated list (like: "Bob,Bill,Fred") and then :N_NameList would be the number of tokens (in above example, 3)
SELECT ... FROM
(
SELECT
REGEXP_SUBSTR(:NameList,'[^,]+',1,LEVEL, 'i') Name
FROM DUAL CONNECT BY LEVEL <= :N_NameList
) x
INNER JOIN PEOPLE ppl
ON ppl.Name LIKE x.Name
...
From what I can tell, it expands out the delimited list into unique rows and then joins it with the following tables for each name, but I'm not sure if that's all it's doing. If that is the case, is there a better way to accomplish this?
You could try this instead:
select ...
from people ppl
where instr (','||:NameList||',',
','||ppl.name||',') > 0;
is there a better way to accomplish this?
Well, you could get rid of N_NameList because you can easily count number of tokens. This doesn't mean that it is a better way, it's just a different option. To be honest, it is probably slower option than yours as I have to calculate something that you entered as a parameter.
As this example is based on SQLPlus, I've used & instead of : for substitution variables. && means that it'll "remember" previously entered value (otherwise, I should type NameList twice.
Your current query:
SQL> select regexp_substr('&namelist', '[^,]+', 1, level, 'i') name
2 from dual
3 connect by level <= &n_namelist;
Enter value for namelist: Bob,Bill,Fred
Enter value for n_namelist: 3
Bob
Bill
Fred
Calculated N_NameList (using REGEXP_COUNT):
SQL> select regexp_substr('&&namelist', '[^,]+', 1, level, 'i') name
2 from dual
3 connect by level <= regexp_count('&&namelist', ',') + 1;
Enter value for namelist: Bob,Bill,Fred
Bob
Bill
Fred
I have (and don't own, so I can't change) a table with a layout similar to this.
ID | CATEGORIES
---------------
1 | c1
2 | c2,c3
3 | c3,c2
4 | c3
5 | c4,c8,c5,c100
I need to return the rows that contain a specific category id. I starting by writing the queries with LIKE statements, because the values can be anywhere in the string
SELECT id FROM table WHERE categories LIKE '%c2%';
Would return rows 2 and 3
SELECT id FROM table WHERE categories LIKE '%c3%' and categories LIKE '%c2%'; Would again get me rows 2 and 3, but not row 4
SELECT id FROM table WHERE categories LIKE '%c3%' or categories LIKE '%c2%'; Would again get me rows 2, 3, and 4
I don't like all the LIKE statements. I've found FIND_IN_SET() in the Oracle documentation but it doesn't seem to work in 10g. I get the following error:
ORA-00904: "FIND_IN_SET": invalid identifier
00904. 00000 - "%s: invalid identifier"
when running this query: SELECT id FROM table WHERE FIND_IN_SET('c2', categories); (example from the docs) or this query: SELECT id FROM table WHERE FIND_IN_SET('c2', categories) <> 0; (example from Google)
I would expect it to return rows 2 and 3.
Is there a better way to write these queries instead of using a ton of LIKE statements?
You can, using LIKE. You don't want to match for partial values, so you'll have to include the commas in your search. That also means that you'll have to provide an extra comma to search for values at the beginning or end of your text:
select
*
from
YourTable
where
',' || CommaSeparatedValueColumn || ',' LIKE '%,SearchValue,%'
But this query will be slow, as will all queries using LIKE, especially with a leading wildcard.
And there's always a risk. If there are spaces around the values, or values can contain commas themselves in which case they are surrounded by quotes (like in csv files), this query won't work and you'll have to add even more logic, slowing down your query even more.
A better solution would be to add a child table for these categories. Or rather even a separate table for the catagories, and a table that cross links them to YourTable.
You can write a PIPELINED table function which return a 1 column table. Each row is a value from the comma separated string. Use something like this to pop a string from the list and put it as a row into the table:
PIPE ROW(ltrim(rtrim(substr(l_list, 1, l_idx - 1),' '),' '));
Usage:
SELECT * FROM MyTable
WHERE 'c2' IN TABLE(Util_Pkg.split_string(categories));
See more here: Oracle docs
Yes and No...
"Yes":
Normalize the data (strongly recommended) - i.e. split the categorie column so that you have each categorie in a separate... then you can just query it in a normal faschion...
"No":
As long as you keep this "pseudo-structure" there will be several issues (performance and others) and you will have to do something similar to:
SELECT * FROM MyTable WHERE categories LIKE 'c2,%' OR categories = 'c2' OR categories LIKE '%,c2,%' OR categories LIKE '%,c2'
IF you absolutely must you could define a function which is named FIND_IN_SET like the following:
CREATE OR REPLACE Function FIND_IN_SET
( vSET IN varchar2, vToFind IN VARCHAR2 )
RETURN number
IS
rRESULT number;
BEGIN
rRESULT := -1;
SELECT COUNT(*) INTO rRESULT FROM DUAL WHERE vSET LIKE ( vToFine || ',%' ) OR vSET = vToFind OR vSET LIKE ('%,' || vToFind || ',%') OR vSET LIKE ('%,' || vToFind);
RETURN rRESULT;
END;
You can then use that function like:
SELECT * FROM MyTable WHERE FIND_IN_SET (categories, 'c2' ) > 0;
For the sake of future searchers, don't forget the regular expression way:
with tbl as (
select 1 ID, 'c1' CATEGORIES from dual
union
select 2 ID, 'c2,c3' CATEGORIES from dual
union
select 3 ID, 'c3,c2' CATEGORIES from dual
union
select 4 ID, 'c3' CATEGORIES from dual
union
select 5 ID, 'c4,c8,c5,c100' CATEGORIES from dual
)
select *
from tbl
where regexp_like(CATEGORIES, '(^|\W)c3(\W|$)');
ID CATEGORIES
---------- -------------
2 c2,c3
3 c3,c2
4 c3
This matches on a word boundary, so even if the comma was followed by a space it would still work. If you want to be more strict and match only where a comma separates values, replace the '\W' with a comma. At any rate, read the regular expression as:
match a group of either the beginning of the line or a word boundary, followed by the target search value, followed by a group of either a word boundary or the end of the line.
As long as the comma-delimited list is 512 characters or less, you can also use a regular expression in this instance (Oracle's regular expression functions, e.g., REGEXP_LIKE(), are limited to 512 characters):
SELECT id, categories
FROM mytable
WHERE REGEXP_LIKE('c2', '^(' || REPLACE(categories, ',', '|') || ')$', 'i');
In the above I'm replacing the commas with the regular expression alternation operator |. If your list of delimited values is already |-delimited, so much the better.
I am developing an application in Oracle APEX. I have a string with user id's that is comma deliminated which looks like this,
45,4932,20,19
This string is stored as
:P5_USER_ID_LIST
I want a query that will find all users that are within this list my query looks like this
SELECT * FROM users u WHERE u.user_id IN (:P5_USER_ID_LIST);
I keep getting an Oracle error: Invalid number. If I however hard code the string into the query it works. Like this:
SELECT * FROM users u WHERE u.user_id IN (45,4932,20,19);
Anyone know why this might be an issue?
A bind variable binds a value, in this case the string '45,4932,20,19'. You could use dynamic SQL and concatenation as suggested by Randy, but you would need to be very careful that the user is not able to modify this value, otherwise you have a SQL Injection issue.
A safer route would be to put the IDs into an Apex collection in a PL/SQL process:
declare
array apex_application_global.vc_arr2;
begin
array := apex_util.string_to_table (:P5_USER_ID_LIST, ',');
apex_collection.create_or_truncate_collection ('P5_ID_COLL');
apex_collection.add_members ('P5_ID_COLL', array);
end;
Then change your query to:
SELECT * FROM users u WHERE u.user_id IN
(SELECT c001 FROM apex_collections
WHERE collection_name = 'P5_ID_COLL')
An easier solution is to use instr:
SELECT * FROM users u
WHERE instr(',' || :P5_USER_ID_LIST ||',' ,',' || u.user_id|| ',', 1) !=0;
tricks:
',' || :P5_USER_ID_LIST ||','
to make your string ,45,4932,20,19,
',' || u.user_id|| ','
to have i.e. ,32, and avoid to select the 32 being in ,4932,
I have faced this situation several times and here is what i've used:
SELECT *
FROM users u
WHERE ','||to_char(:P5_USER_ID_LIST)||',' like '%,'||to_char(u.user_id)||',%'
ive used the like operator but you must be a little carefull of one aspect here: your item P5_USER_ID_LIST must be ",45,4932,20,19," so that like will compare with an exact number "',45,'".
When using it like this, the select will not mistake lets say : 5 with 15, 155, 55.
Try it out and let me know how it goes;)
Cheers ,
Alex
Create a native query rather than using "createQuery/createNamedQuery"
The reason this is an issue is that you cannot just bind an in list the way you want, and just about everyone makes this mistake at least once as they are learning Oracle (and probably SQL!).
When you bind the string '32,64,128', it effectively becomes a query like:
select ...
from t
where t.c1 in ('32,64,128')
To Oracle this is totally different to:
select ...
from t
where t.c1 in (32,64,128)
The first example has a single string value in the in list and the second has a 3 numbers in the in list. The reason you get an invalid number error is because Oracle attempts to cast the string '32,64,128' into a number, which it cannot do due to the commas in the string.
A variation of this "how do I bind an in list" question has come up on here quite a few times recently.
Generically, and without resorting to any PLSQL, worrying about SQL Injection or not binding the query correctly, you can use this trick:
with bound_inlist
as
(
select
substr(txt,
instr (txt, ',', 1, level ) + 1,
instr (txt, ',', 1, level+1) - instr (txt, ',', 1, level) -1 )
as token
from (select ','||:txt||',' txt from dual)
connect by level <= length(:txt)-length(replace(:txt,',',''))+1
)
select *
from bound_inlist a, users u
where a.token = u.id;
If possible the best idea may be to not store your user ids in csv! Put them in a table or failing that an array etc. You cannot bind a csv field as a number.
Please dont use: WHERE ','||to_char(:P5_USER_ID_LIST)||',' like '%,'||to_char(u.user_id)||',%' because you'll force a full table scan although with the users table you may not have that many so the impact will be low but against other tables in an enterprise environment this is a problem.
EDIT: I have put together a script to demonstrate the differences between the regex method and the wildcard like method. Not only is regex faster but it's also a lot more robust.
-- Create table
create table CSV_TEST
(
NUM NUMBER not null,
STR VARCHAR2(20)
);
create sequence csv_test_seq;
begin
for j in 1..10 loop
for i in 1..500000 loop
insert into csv_test( num, str ) values ( csv_test_seq.nextval, to_char( csv_test_seq.nextval ));
end loop;
commit;
end loop;
end;
/
-- Create/Recreate primary, unique and foreign key constraints
alter table CSV_TEST
add constraint CSV_TEST_PK primary key (NUM)
using index ;
alter table CSV_TEST
add constraint CSV_TEST_FK unique (STR)
using index;
select sysdate from dual;
select *
from csv_test t
where t.num in ( Select Regexp_Substr('100001, 100002, 100003 , 100004, 100005','[^,]+', 1, Level) From Dual
Connect By Regexp_Substr('100001, 100002,100003, 100004, 100005', '[^,]+', 1, Level) Is Not Null);
select sysdate from dual;
select *
from csv_test t
where ('%,' || '100001,100002, 100003, 100004 ,100005' || ',%') like '%,' || num || ',%';
select sysdate from dual;
select *
from csv_test t
where t.num in ( Select Regexp_Substr('100001, 100002, 100003 , 100004, 100005','[^,]+', 1, Level) From Dual
Connect By Regexp_Substr('100001, 100002,100003, 100004, 100005', '[^,]+', 1, Level) Is Not Null);
select sysdate from dual;
select *
from csv_test t
where ('%,' || '100001,100002, 100003, 100004 ,100005' || ',%') like '%,' || num || ',%';
select sysdate from dual;
drop table csv_test;
drop sequence csv_test_seq;
Solution from Tony Andrews works for me. The process should be added to "Page processing" >> "After submit">> "Processes".
As you are Storing User Ids as String so You can Easily match String Using Like as Below
SELECT * FROM users u WHERE u.user_id LIKE '%'||(:P5_USER_ID_LIST)||'%'
For Example
:P5_USER_ID_LIST = 45,4932,20,19
Your Query Surely Will return Any of 1 User Id which Matches to Users table
This Will Surely Resolve Your Issue , Enjoy
you will need to run this as dynamic SQL.
create the entire string, then run it dynamically.