I know it is a silly question and may be already answered somewhere, please guide me to the link if it is.
I want to print a column which is not included in group by clause. Oracle says that it should be included in group by expression, but I want value to be from the same row from which max() value for the other column was selected.
For example: if I have a table with following columns:
Employee_Name, Action_code, Action_Name
I want to see the name of action with maximum action_code for each employee, also I cannot use subquery in the condition.
I want some thing like this:
select employee_name, max(action_code), action_name --for max code
from emp_table
group by employee_name
This action_name in select statement is causing problem, if I add action_name in group by clause then it will show action name for each action for each employee, which will make the query meaningless.
Thanks for support
You can use a keep .. last pattern:
select employee_name,
max(action_code) as action_code,
max(action_name) keep (dense_rank last order by action_code) as action_name
from emp_table
group by employee_name
The documentation explains this more fully under the sister function first().
Related
As the question states, I'm trying to save calculated data, that is the result of a select statement, to another table. In this Image, the column with green outline is a database column and the columns with red outline are calculated based on that column, I want to save the Red outlined columns to another table where the column names would be same.
This looks like a classic report. Is it? If so, it is result of a select statement. As it calculates all values you're interested in, you'd use it in an insert statement. For example, you could create a button and create a process that fires when that button is pressed. It would then
insert into target_table (emp_id, salary, house_rent, ...)
select emp_id, ... whatever you select in report's query
from ...
However: data changes. What will you do when something - that is used to calculate those values - is changed? Will you delete those rows and insert new ones? Update existing values? Add yet another row?
If you'd update existing values, consider using merge as it is capable of inserting rows (in when not matched clause, in your case) , as well as updating rows (in when matched). That would look like this:
merge into target_table t
using (select emp_id, ... whatever you select in report's query
from ...
) x
on (t.emp_id = x.emp_id)
when matched then update set
t.salary = x.salary,
t.house_rent = x.house_rent,
...
when not matched then insert (emp_id, salary, house_rent, ...)
values (x.emp_id, x.salary, x.house_rent, ...);
You can use the INSERT INTO SELECT statement - plenty of examples available on google
INSERT INTO another_table (
emp_id,
col1,
col2
)
SELECT emp_id,
calculated_col1,
calculated_col2
FROM first_table
I'm a student and this is my first year of learning Oracle SQL. On the exam, I used this code:
SELECT department_id,MAX(salary)
FROM employees
GROUP BY department_id
HAVING INSTR(TO_CHAR(department_id),'5')!=1 AND MAX(salary)<1000;
and the professor said that I should be using something like
SELECT DEPARTMENT_ID, MAX(SALARY)
FROM EMPLOYEES
WHERE SUBSTR(TO_CHAR(DEPARTMENT_ID),1,1)<>'5'
GROUP BY DEPARTMENT_ID
HAVING MAX(SALARY) < 1000;
We got the same table so my question is when these two can display different results. I'm aware that data processing is different but as he said that was not the problem. The problem is not is using the INSTR function but not using WHERE.
The Where clause workn on the raw contents of the rows
so you filter the dataset that is evaluated for the select clause
WHERE SUBSTR(TO_CHAR(DEPARTMENT_ID),1,1)<>'5'
don't select the rows with
SUBSTR(TO_CHAR(DEPARTMENT_ID),1,1)='5'
so these rows are not used for
SELECT DEPARTMENT_ID, MAX(SALARY) ..GROUP BY DEPARTMENT_ID
HAVING work on the result of the selected result so also the rows with SUBSTR(TO_CHAR(DEPARTMENT_ID),1,1)='5' should be processed
in your case each value for the column DEPARTMENT_ID is always selected because is mentioned in group by and then both the query should return the same result
Given the syntax:
CREATE [OR REPLACE] FUNCTION [Owner.]FunctionName
[(arguments [IN|OUT|IN OUT][NOCOPY] DataType [DEFAULT expr][,...])]
RETURN DataType [InvokerRightsClause] [DETERMINISTIC]
{IS|AS}
I think my query is syntactically correct, but for some reason, I get these errors during compilation:
Error(6,5): PL/SQL: SQL Statement ignored
Error(8,34): PL/SQL: ORA-00942: table or view does not exist
CREATE or replace FUNCTION aCombinationMismatches(p_column1 IN VARCHAR2)
RETURN Number
IS
duplicate_count NUMBER(4,0);
BEGIN
select count(*) into duplicate_count
from schema1.tableA a
inner join schema1.tableB b
on a.b_id = b.id and a.column1 = p_column1
group by a.b_id, a.column1, a.column2, b.column1, b.column2, b.column3;
return duplicate_count;
END;
Anyone see anything wrong with my query above?
Also I'd like to how to set this UDF up to be used to create a CHECK constraint. How exactly do I specify the param: p_param1 to the function assuming this is the value of a field column1 in a row that a user is trying to insert? I just don't want the user to insert a record into tableA that consists of duplicate combinations of fields across tables: tableA and tableB.
Note: The tables tableA and tableB do exist - a select query like below indicates it. So the error above is rather confusing to me, I must add. (All table and column names in the two queries were found/replaced with dummy values.)
select count(*)
from schema1.tableA a
inner join schema1.tableB b
on a.b_id = b.id
group by a.b_id, a.column1, a.column2, b.column1, b.column2, b.column3;
Output:
Count(*)
OK, you already know that you have problem with priviliges. I wanted to add that you won't be able to create CHECK constraint basing on your function. According to documentation:
The condition of a check constraint can refer to any column in the table, but it cannot refer to columns of other tables.
Conditions of check constraints cannot contain the following constructs:
Subqueries and scalar subquery expressions
Calls to the functions that are not deterministic (CURRENT_DATE, CURRENT_TIMESTAMP, DBTIMEZONE, LOCALTIMESTAMP, SESSIONTIMEZONE, SYSDATE, SYSTIMESTAMP, UID, USER, and USERENV)
Calls to user-defined functions
So to achieve what you want, you would have to define some triggers, or make use of some combination of MATERIALIZED VIEW and CHECK constraint. See for example this discussion on Ask Tom
You probably have access to TableA and TableB through a Role. This means that you can query the table, but you cannot create a procedure that reads or writes that table. In order to compile your procedure you should at least grant select on the table to your user.
In the link below you'll find more info
https://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:1065832643319
I know the title is saying nothing... but the argument is a little "complex" to explain in a single row.
All the code i'm writing is just an example, my current code is from other table etc, but the behaviour is the same.
i have defined a cursor like this:
CURSOR emp_cur (l_type)
IS
with emp_general AS (select *
from emp
where type = l_type),
emp_active AS (select *
from emp_geral
where status = ACTIVE_STATUS),
emp_inactive AS (select *
from emp_general
where status = INACTIVE_STATUS)
select distinct name, department
from emp_active
minus
select distinct name, department
from emp_inactive;
This cursor take a parameter for filter emp type and make a minus to fetch ACTIVE - INACTIVE emp.
This cursor return name and department.
Now have to declare different cursor with different "select" statemant, for example:
select location
from emp_active
select location
from emp_active
I would like to dont duplicate my cursor just to change the select. There is a way to do this and avoid code duplication (withuout using DynamicSQL - Difficult to debug in production enviroment)?
You could create two Global temporary tables explicitly once(not on the fly):
emp_active_gtt
emp_inactive_gtt
Such that, each temp table will have the entire result set of active and inactive records respectively.
For example, in the code you would do:
insert into emp_active_gtt
select *
from ....
where status ='ACTIVE'
Similarly, for inactive records:
insert into emp_inactive_gtt
select *
from ....
where status ='INACTIVE'
You could now use the two tables in the scope of the session anywhere to get the required rows.
Read more about GTT in the documentation here https://docs.oracle.com/database/121/SQLRF/statements_7002.htm#i2153132
I have specifiec requirement .Actually this is my query. here amount is a column in my table.but i did not mention the amount column in select statement.here can i use this column in oreder by clause.
SELECT stud_name, stud_roll, stud_prg
FROM programcl
ORDER BY 3, amount, 1;
Yes, you can mix both positional and named assignments in your ORDER BY clause.
The positional assignments must appear in your SELECT list. The named assignments do not have to.
can i use this column in oreder by clause.
Yes of course you can use a different column in order by clause that wasn't selected from your select statement.
For example
select col1 from tab1
order by col2;
by this way you get results from col1 which will be displayed on order of col2.
Its Worth trying