I'm trying to display at oracle apex IR query, a biggest date from 3 different tables, using greatest function to choice the biggest. For that, created two varchar2 type functions.
One of them return the date converted to char, of a selected table like this:
create or replace FUNCTION RETURN_DATES (key in number, parameter in NUMBER)
RETURN VARCHAR2 IS
...
BEGIN
case parameter
when 1 then
select distinct MAX(mydate) into seal from table1 v WHERE v.num_contract = number_contract;
return NVL(TO_CHAR(TO_DATE (seal),'mm/dd/yyyy'),'01/01/1980')
when 2 then
select... from table2 x WHERE...
...
END;
The second function calls that one using a greatest function between the parameter calls, which refers to case statement:
create or replace FUNCTION RETURN_BIGGEST_DATE(key in number) return VARCHAR2 IS
...
BEGIN
select greatest (RETURN_DATES(key,1),RETURN_DATES(key,2),RETURN_DATES(key,3)) into greatest_date from dual;
return greatest_date;
...
END;
When i call it on sql commands it's works fine, but at an interactive report its fails, returning the ORA-1843, using the quite same query.
Could anyone help?
Simply modifying the RETURN_DATES returning DATE
and the seal variable, of date type, without conversions, works fine at apex IR!
I noticed when a date column is relayed on ir query, there are an extra parameter on Column filter, named Date Ranges. It was the two way traffic to start simulations and change the returning type of the that function.
No more changes was required:
create or replace FUNCTION RETURN_DATES (key in number, parameter in NUMBER)
RETURN DATE IS
...
select distinct MAX(mydate) into seal from table1 v WHERE v.num_contract = number_contract;
return NVL(seal),'01/01/1980')
Related
In my schema, I have a reference number column in my settlement
table with a null value of varchar2 type, that I want to update it continuously.
Then I've created a sequence called ref_seq_num using a built-in function.
I want to use it (ref_seq_num) within my function get_ref_num to update the sequence ref. number to my settlement table,
which the return type also is varchar2 and I have a function like below
CREATE OR REPLACE FUNCTION get_ref_num RETURN settlement.ref_nr %TYPE IS
v_ref_seq settlement.ref_nr%TYPE;
BEGIN
v_ref_seq := to_char(sysdate, 'YYYYMMDD')||LPAD(ref_seq_num.nextval, 8,'0');
RETURN v_ref_seq;
END get_ref_num;
However, I bum into this error message 1/55 PLS-00302: component 'ref_nr' must be declared. I also tried changing the data type to varchar2 and error message is PLS-00215: String length constraints must be in range (1 .. 32767) How can I fix it?
According to your code, it seems that there's a table whose name is SETTLEMENT, but it doesn't contain the REF_NR column.
The following example shows how to do that:
SQL> create sequence ref_seq_num;
Sequence created.
A table that does contain the REF_NR column (which is then used in the function):
SQL> create table settlement (ref_nr varchar2(20));
Table created.
Your code, unmodified:
SQL> CREATE OR REPLACE FUNCTION get_ref_num RETURN settlement.ref_nr %TYPE IS
2 v_ref_seq settlement.ref_nr%TYPE;
3 BEGIN
4 v_ref_seq := to_char(sysdate, 'YYYYMMDD')||LPAD(ref_seq_num.nextval, 8,'0');
5 RETURN v_ref_seq;
6 END get_ref_num;
7 /
Function created.
Testing:
SQL> select get_ref_num from dual;
GET_REF_NUM
--------------------------------------------------------------------------------
2019050400000001
SQL>
If you have a column called ref_nr within settlement table, you code must work properly. I think the problem in the second case raises due to missing data precision part ( should be such as varchar2(16) ) for defining the variable as v_ref_seq varchar2. I would prefer using a numeric type such as number or int to hold the values for ref_nr, since they are all numeric, and this data type protects the data remain as numeric. Whenever you need to query you may use to_char function preventing exponential display( select to_char(ref_nr) from settlement ).
Moreover, if you use Oracle 12c version, you don't need to create such an extra function, just alter your table so that being sequence as your default for the column :
alter table settlement
modify ref_nr default to_char(sysdate, 'yyyymmdd')||lpad(ref_seq_num.nextval, 8,'0');
I need to get the year from a date in all of the records in an Oracle database. The following is my attempt:
CREATE or replace TYPE BODY student_t AS MEMBER FUNCTION getYear RETURN NUMBER IS
yearDOB NUMBER;
BEGIN
SELECT EXTRACT(YEAR FROM s.dob) INTO yearDOB
from student s;
return yearDOB;
END;END;/
But that will not work when the table has more than 1 record.
How I can fix the issue?
When you do select into rdbms thinks that only one value will be returned, or that your variable will be an array. You cannot set a NUMBER variable to an array of objects.
I have function which returns column names and i am trying to use the column name as part of my select statement, but my results are coming as column name instead of values
FUNCTION returning column name:
get_col_name(input1, input2)
Can И use this query to the results of the column from table -
SELECT GET_COL_NAME(input1,input2) FROM TABLE;
There are a few ways to run dynamic SQL directly inside a SQL statement. These techniques should be avoided since they are usually complicated, slow, and buggy. Before you do this try to find another way to solve the problem.
The below solution uses DBMS_XMLGEN.GETXML to produce XML from a dynamically created SQL statement, and then uses XML table processing to extract the value.
This is the simplest way to run dynamic SQL in SQL, and it only requires built-in packages. The main limitation is that the number and type of columns is still fixed. If you need a function that returns an unknown number of columns you'll need something more powerful, like the open source program Method4. But that level of dynamic code gets even more difficult and should only be used after careful consideration.
Sample schema
--drop table table1;
create table table1(a number, b number);
insert into table1 values(1, 2);
commit;
Function that returns column name
create or replace function get_col_name(input1 number, input2 number) return varchar2 is
begin
if input1 = 0 then
return 'a';
else
return 'b';
end if;
end;
/
Sample query and result
select dynamic_column
from
(
select xmltype(dbms_xmlgen.getxml('
select '||get_col_name(0,0)||' dynamic_column from table1'
)) xml_results
from dual
)
cross join
xmltable
(
'/ROWSET/ROW'
passing xml_results
columns dynamic_column varchar2(4000) path 'DYNAMIC_COLUMN'
);
DYNAMIC_COLUMN
--------------
1
If you change the inputs to the function the new value is 2 from column B. Use this SQL Fiddle to test the code.
I have a type called sell_type defined as
CREATE OR REPLACE TYPE sell_type AS OBJECT (
dname VARCHAR (50),
car_model VARCHAR(20),
make VARCHAR (20),
price NUMBER (10,2),
MEMBER FUNCTION total_sales RETURN NUMBER
);
/
Body:
CREATE OR REPLACE TYPE BODY sell_type AS
MEMBER FUNCTION total_sales RETURN NUMBER IS
BEGIN
RETURN SELF.price;
END total_sales;
END;
/
And an object table
CREATE TABLE sell of Sell_Type;
/
I want to get the total sales for a given seller with something like:
select s.total_sales() from sell s
where s.dname = 'John Doe';
But what I get is a separate list of prices of all the sales of that given seller, rather than the total of those prices.
I know that I have to fix my type body somehow. I tried to use the SUM() inside the return but that didn't work. Can someone please help?
Summing is an aggregation, a set function. A Type is a single thing; it is not possible for a Type instance to execute an aggregation across all the instances of its peers.
If you want to do such a thing you would need to declare a new type, with a signature like this:
CREATE OR REPLACE TYPE sell_set AS OBJECT (
sell_items sell_type,
MEMBER FUNCTION total_sales (p_seller varchar2) RETURN NUMBER
);
/
Writing the body for this type is left as an exercise for the reader ;-)
Note that Oracle SQL and PL/SQL do work with OO concepts but in a clunky fashion. It's fine to explore the syntax for educational purposes, if only to learn its limitations. But there are a very narrow set of use cases in real life. A relational data model is the far superior way of storing data.
This body will do the trick. But it will return the same value for each row on the sell table. Therefore, you have to use 'group by' or 'max()' if you want to see just one row of result.
CREATE OR REPLACE
TYPE BODY SELL_TYPE AS
MEMBER FUNCTION total_sales (p_seller varchar2) RETURN NUMBER IS
total_price NUMBER;
BEGIN
SELECT sum(s.price) INTO total_price FROM sell s where s.dname = p_seller;
RETURN total_price;
END total_sales;
END;
/
select query will look like this.
select s.total_sales('John')
from sell s GROUP BY s.total_sales('John');
As the title said : I want to create a type in oracle based on an existing Table.
I did as follow :
create or replace type MY_NEW_TYPE as object( one_row EXISTING_TABLE%rowtype);
The Aim is to be able to use this into a function which will return a table containing sample row of the table EXISTING_TABLE :
create or replace function OUTPUT_FCT() return MY_NEW_TYPE AS
...
If you only need to create a function that returns a row from your table, you could try something like the following, without creating types.
setup:
create table EXISTING_TABLE( a number, b varchar2(100));
insert into EXISTING_TABLE values (1, 'one');
function:
create or replace function OUTPUT_FCT return EXISTING_TABLE%rowtype AS
retVal EXISTING_TABLE%rowType;
begin
select *
into retVal
from EXISTING_TABLE
where rownum = 1;
--
return retVal;
end;
function call
SQL> begin
2 dbms_output.put_line(OUTPUT_FCT().a);
3 dbms_output.put_line(OUTPUT_FCT().b);
4 end;
5 /
1
one
However, I would not recommend such an approach, because things like select * can be really dangerous; I would much prefer defining a type with the fields I need, and then explicitly query my table for the needed columns.
No, you can't do that, you'll get a compilation error:
create or replace type my_new_type as object(one_row t42%rowtype);
/
Type MY_NEW_TYPE compiled
Errors: check compiler log
show errors
Errors for TYPE STACKOVERFLOW.MY_NEW_TYPE:
LINE/COL ERROR
-------- -----------------------------------------------------------------------
0/0 PL/SQL: Compilation unit analysis terminated
1/36 PLS-00329: schema-level type has illegal reference to MYSCHEMA.T42
You will need to specify each field in the object type, and you will have to specify the data types manually too - you can't use table.column%type either.
You could create the type dynamically based on column and data type information from the data dictionary, but as this will (hopefully) be a one-off task and not something you'd do at runtime, that doesn't really seem worth it.
You can create a PL/SQL table type based on your table's rowtype, but you would only be able to call a function returning that from PL/SQL, not from plain SQL - so you couldn't use it in a table collection expression for example. If you were only returning a single sample row you could return a record rather than a table, but the same applies. You can also have a function that returns a ref cursor which could match the table's structure, but you wouldn't be able to treat that as a table either.
Read more about object type creation in the documentation. Specifically the attribute and datatype sections.