New to Oracle, having loads of niggling troubles, strong in tSQL not in pl\SQL
I want to list the contents of a table in SQL Developer dependant on some pre-programmed variables, ultimately I would like this to be like a MS-SQL Stored Procedure where I call it passing parameters...
I get error ...an INTO clause is expected in this SELECT statement
TIA - Andy
DECLARE
tbl_name varchar2(30) := 'ALL';
ix_name varchar2(30) := 'ALL';
BEGIN
SELECT table_name, index_name, monitoring
FROM v$object_usage
WHERE (table_name = UPPER(tbl_name) or UPPER(tbl_name) = 'ALL')
AND (index_name = UPPER(ix_name) or UPPER(ix_name) = 'ALL');
END;
You get this error because your select is fetching some data but you're not storing it into any variable.
Your select should be like,
SELECT table_name, index_name, monitoring
into var1,var2,var3
FROM v$object_usage
But if your select returns more than one rows this will throw an error, so you might have to use collections in that case.
Related
I want to pass a table name and schema into a procedure, and have it generate insert, update and delete statements for the particular table. This is part of an automated testing solution (in a development environment) in which I need to test some change data capture. I want to make this dynamic as it is going to be need to be done for lots of different tables over a long period of time, and I need to call it via a REST request through ORDS, so don't want to have to make an endpoint for every table.
Update and delete are fairly easy, however I am struggling with the insert statement. Some of the tables being passed in have hundreds of columns with various constraints, fks etc. so I think it makes sense to just manipulate an existing record by changing only the primary key. I need to be able to modify the primary key to a new value known to me beforehand (e.g. '-1').
Ideally I would create a dynamic rowtype, and select into where rownum = 1, then loop round the primary keys found from all_constraints, and update the rowtype.pk with my new value, before inserting this into the table. Essentially the same as this but without knowing the table in advance.
e.g. rough idea
PROCEDURE manipulate_records(p_owner in varchar2, p_table in varchar2)
IS
cursor c_pk is
select column_name
from all_cons_columns
where owner = p_owner
and constraint_name in (select constraint_name
from all_constraints
where table_name = p_table
and constraint_type = 'P');
l_row tbl_passed_in%ROWTYPE --(I know this isn't possible but ideally)
BEGIN
-- dynamic sql or refcursor to collect a record
select * into tbl_passed_in from tablename where rownum = 1;
-- now loop through pks and reassign their values to my known value
for i in c_pk loop
...if matches then reassign;
...
end loop;
-- now insert the record into the table passed in
END manipulate_records;
I have searched around but haven't found any examples which fit this exact use case, where an unknown column needs to be modified and insert into a table.
Depending on how complex your procedure is, you might be able to store it as a template in a CLOB. Then pull it in, replace table and owner, then compile it.
DECLARE
prc_Template VARCHAR2(4000);
vc_Owner VARCHAR2(0008);
vc_Table VARCHAR2(0008);
BEGIN
vc_Table := 'DUAL';
vc_Owner := 'SYS';
-- Pull code into prc_Template from CLOB, but this demonstrates the concept
prc_Template := 'CREATE OR REPLACE PROCEDURE xyz AS r_Dual <Owner>.<Table>%ROWTYPE; BEGIN NULL; END;';
prc_Template := REPLACE(prc_Template,'<Owner>',vc_Owner);
prc_Template := REPLACE(prc_Template,'<Table>',vc_Table);
-- Create the procedure
EXECUTE IMMEDIATE prc_Template;
END;
Then you have the appropriate ROWTYPE available:
CREATE OR REPLACE PROCEDURE xyz AS r_Dual SYS.DUAL%ROWTYPE; BEGIN NULL; END;
But you can't create the procedure and run it in the same code block.
I need this piece of code in a stored procedure so I can pass an array of ids and update the related records. I am wondering whether I have to use the loop rather than use an IN clause in the sp.
SET SERVEROUTPUT ON
DECLARE
P_IDS PKGINFO.t_ids; --type: table of NUMBER index by pls_integer;
P_RESULT NUMBER;
BEGIN
p_IDS(1) := 12345;
--this works fine:
for i in ( select * from table(p_ids))
loop
UPDATE TABLE1
SET FD1 = 'test'
WHERE P_ID = i.column_value;
end loop;
--this works fine too:
SELECT COUNT(*) INTO p_RESULT FROM TABLE1
WHERE P_ID IN (SELECT * FROM TABLE (p_ids));
--but this does not work, why????? how to make it work?
UPDATE TABLE1
SET FD1 = 'test'
WHERE P_ID IN (SELECT * FROM TABLE (p_ids));
END;
--==================PKGINFO.t_ids==================
CREATE OR REPLACE package dbname.PKGINFO as
-- package created to perform Associative array calls
type t_ids is table of NUMBER index by pls_integer;
end PKGINFO;
/
I expected the UPDATE can use IN clause, but it gives me an INVALID TYPE error.
Until fairly recently Oracle didn't allow PL/SQL types in SQL statements, including in a table collection expression. You seem to be using a version where support has been added for select but not (yet) for update. If you had one available then you could use a schema-level type. Also have a look at member of.
With the type you have now you could use FORALL, which would be more efficient than a loop with individual updates::
FORALL i IN p_ids.first..p_ids.last
UPDATE TABLE1
SET FD1 = 'test'
WHERE P_ID = p_ids(i);
Is there a way to capture the count in a collection table for a certain condition.
For example :
SELECT COUNT(*)
BULK COLLECT INTO v_cnt
FROM tt_product
WHERE region = 'NA';
The above query throws error saying:
Error(649,13): PL/SQL: ORA-00942: table or view does not exist
Any insights would be highly appreciated .
Thanks
Firstly, remove BULK COLLECT, you are getting a single value...
Secondly, if I understand you right, and you are talking about the collection of e.g. type
CREATE OR REPLACE T AS TABLE OF ...
then wrap the name with the table() keyword
SELECT COUNT(*)
INTO v_cnt
FROM table(tt_product)
WHERE region = 'NA';
Dump your results into a #TEMP table first then do your count from there.
Something like:
SELECT * BULK COLLECT INTO #TEMP
FROM tt_product
Where region = 'NA'
SELECT COUNT(*) FROM #TEMP
This is untested so you might have to play with it a little to get it to work.
My example is for SQL Server, you'll have to find the equivalent for ORACLE as I'm not as familiar with it.
declare
b l_number := new l_number(1,2,3,4); -- type L_number is table of number ;
v1 number;
v2 number;
begin
select count(*) into v1 from table(b);
select CARDINALITY(b) into v2 from dual;
dbms_output.put_line(v1);
dbms_output.put_line(v2);
end;
In SQL Server we can use this:
DECLARE #variable INT;
SELECT #variable= mycolumn from myTable;
How can I do the same in Oracle? I'm currently attempting the following:
DECLARE COMPID VARCHAR2(20);
SELECT companyid INTO COMPID from app where appid='90' and rownum=1;
Why this is not working?
SELECT INTO
DECLARE
the_variable NUMBER;
BEGIN
SELECT my_column INTO the_variable FROM my_table;
END;
Make sure that the query only returns a single row:
By default, a SELECT INTO statement must return only one row. Otherwise, PL/SQL raises the predefined exception TOO_MANY_ROWS and the values of the variables in the INTO clause are undefined. Make sure your WHERE clause is specific enough to only match one row
If no rows are returned, PL/SQL raises NO_DATA_FOUND. You can guard against this exception by selecting the result of an aggregate function, such as COUNT(*) or AVG(), where practical. These functions are guaranteed to return a single value, even if no rows match the condition.
A SELECT ... BULK COLLECT INTO statement can return multiple rows. You must set up collection variables to hold the results. You can declare associative arrays or nested tables that grow as needed to hold the entire result set.
The implicit cursor SQL and its attributes %NOTFOUND, %FOUND, %ROWCOUNT, and %ISOPEN provide information about the execution of a SELECT INTO statement.
Not entirely sure what you are after but in PL/SQL you would simply
DECLARE
v_variable INTEGER;
BEGIN
SELECT mycolumn
INTO v_variable
FROM myTable;
END;
Ollie.
One Additional point:
When you are converting from tsql to plsql you have to worry about no_data_found exception
DECLARE
v_var NUMBER;
BEGIN
SELECT clmn INTO v_var FROM tbl;
Exception when no_data_found then v_var := null; --what ever handle the exception.
END;
In tsql if no data found then the variable will be null but no exception
ORA-01422: exact fetch returns more than requested number of rows
if you don't specify the exact record by using where condition, you will get the above exception
DECLARE
ID NUMBER;
BEGIN
select eid into id from employee where salary=26500;
DBMS_OUTPUT.PUT_LINE(ID);
END;
For storing a single row output into a variable from the select into query :
declare v_username varchare(20);
SELECT username into v_username FROM users WHERE user_id = '7';
this will store the value of a single record into the variable v_username.
For storing multiple rows output into a variable from the select into query :
you have to use listagg function. listagg concatenate the resultant rows of a coloumn into a single coloumn and also to differentiate them you can use a special symbol.
use the query as below
SELECT listagg(username || ',' ) within group (order by username) into v_username FROM users;
I can't seem to get variables to work in an Oracle PL/SQL where clause. I come from a Microsoft SQL Server background and there it was easy. For example, what would be all steps needed to do something similar to the following?
declare #var int set #var = 1
select * from SomeTable where SomeField = #var
This doesn't seem like it should be hard in PL/SQL, but evidently it is. :-/ I hear I need to use cursors and the like in PL/SQL?
Any help would be greatly appreciated. Thanks.
What do you want to do with the data that the SELECT returns? If you just want to see it you don't need PL/SQL at all, just do this in SQL Plus:
variable var number
exec :var := 1
select * from SomeTable where SomeField = :var;
Or in a tool like SQL Developer or Toad, just do this:
select * from SomeTable where SomeField = :var;
and it will prompt you to enter the value for :var.
The following code declares a variable var to use in the WHERE clause, and a variable result to put the result in then executes it inside a PL/SQL block.
DECLARE
var INT := 1;
result INT;
BEGIN
SELECT 123
INTO result
FROM DUAL
WHERE var = 1;
DBMS_OUTPUT.put_line (var);
DBMS_OUTPUT.put_line (result);
END;
The DBMS_OUTPUT.PUT_LINE calls make it produce this DBMS output:
1
123
declare
type t_rec is record
(
col1 number,
col2 myTable.col2%type
);
v_rec t_rec;
type t_tab is table of v_rec%type index by binary_integer;
v_tab t_tab;
begin
select col1, col2
bulk collect into v_tab
from myTable
where col3 = 'BLAH';
-- do something great with v_tab...
end;
Also know that if you try to select into (or bulk collect into) a variable and no rows are returned, you'll get a no_data_found exception, so you may want to handle that situation.
See more here on pl/sql collections. Above uses an associative array, but there are nested tables and varrays as well. Again, see the link.
Hope that helps.
I use it like this
select * from sec_mainmenu where serno = '&MENU_ID';
When you run it, pl/sql will prompt for MENU_ID value.