I'm using Oracle SQL Developer to test a query to be used in an ADF application's read only view object. ADF documentation recommends using an uppercase letter to begin the name of a bind variable. So... I've creatively named mine :BindVariable
Funky part is SQL Developer appears to dislike bind variables that begin with an upper case letter.
This query works
select * from tablename
where id like :bindVariable
This one does not
select * from tablename
where id like :BindVariable
Am I correct in understanding that bind variable names cannot begin with an upper case letter? Or is there something else amiss here?
EDIT
Is this just an Oracle SQL Developer thing? :BindVariable works just fine in JDeveloper's database navigator.
Thanks for reading! Any input will be greatly appreciated.
Oracle SQL Developer: can bind variables begin with upper case letter?
Yes.
There is no issue with SQL Developer. I have tested it on version 3.2.20.10
Please see the screenshots:
Query:
Result:
No issues in SQL*Plus either:
SQL> variable BindVariable VARCHAR2(20)
SQL> EXEC :BindVariable := 'SMITH'
PL/SQL procedure successfully completed.
SQL> SELECT empno FROM emp WHERE ename LIKE :BindVariable;
EMPNO
----------
7369
SQL>
Related
Create or replace procedure sp_create_tables as
Lv_str varchar2(1000);
Begin
For I in (select distinct(deptno) from emp) loop
Lv_str:='create table deptno'||I||' select * from emp where
1=2';
Execute immediate lv_str;
End loop;
End;
From what I can understand, your question is probably "why the procedure throws this compilation error"
PLS-00306: wrong number or types of arguments in call to '||'
The reason is that the implicit cursor loop variable I refers to the set of records from the query and not the deptno itself. In order to refer to the deptno, you should use <loop_variable>.deptno. Also 2 other things you should change: The as keyword is missing and DISTINCT is a keyword and you are using it as a function, which works because of default parentheses, but is not the right way to use it.
Create or replace procedure sp_create_tables as
Lv_str varchar2(1000);
Begin
For I in (select distinct dept from emp) loop
Lv_str:='create table deptno'||I.deptno||' as select * from emp where
1=2';
Execute immediate lv_str;
End loop;
End;
In this line of code I is an implicit rowtype variable, with a data structure defined by the projection of the driving select statement:
For I in (select distinct(deptno) from emp) loop
But you are attempting to reference it in your dynamic SQL as though it were an attribute. You need to use a column name instead.
Create or replace procedure sp_create_tables as
Lv_str varchar2(1000);
Begin
For I in (select distinct (deptno) from emp) loop
Lv_str:='create table deptno'|| I.deptno ||
' as select * from emp where 1=2';
Execute immediate lv_str;
End loop;
End;
Incidentally there is a bug in your dynamic SQL statement. The correct syntax is CREATE TABLE ... AS SELECT .... Dynamic SQL is hard because the compiler can't validate the bits of code in strings. Consequently what should be compilation errors manifest themselves as runtime errors. You will find it helpful to instrument your code with some logging (or dbms_output.put_line()) to record the assembled statement before it runs. It makes debugging a lot easier.
" i have got a error saying -01031 insufficient priviliges"
So what this means is your authorisation to create a table was granted through a role. The Oracle security model does not allow us to build PL/SQL programs - or views - using privileges granted through a role. This includes PL/SQL executing DDL through dynamic SQL. You need a DBA user to grant CREATE TABLE to your user directly.
I've created the following procedure
Create or replace procedure abcd
(
tab_name in USER_TABLES.table_name%type
)
is
begin
execute immediate
'select * from'||tab_name;
end abcd;
The procedure gets compiled.
I am trying to get the output using the following
select abcd('Table') from dual ;
I am new to dynamic SQL and this does not seem to work for me. I keep getting the error
[Error] Execution (44: 8): ORA-00904: "ABCD": invalid identifier
Can someone please help ?
Regards,
Kshitij
You're missing a space before your table name:
create or replace procedure abcd (tab_name in USER_TABLES.table_name%type )
is
begin
execute immediate 'select * from '||tab_name;
end abcd;
This won't work because you're trying to call it as a function, not a procedure:
select abcd('Table') from dual ;
Your second attempt should now work:
exec abcd('Table');
... but will now get a different error. In PL/SQL you have to select into something. In this case you probably want to open a cursor with the dynamic string and do something with the results. Not really sure what your end goal is though.
You should also read up about SQL injection while you learn about dynamic SQL.
you cannot perform a select on a procedure, a function will work only if single record return.
use
begin
abcd();
end;
or use
execute keyword
ALSO use a space after from in query
It will not work.
When you invoke EXECUTE IMMEDIATE the sql statement is send to SQL engine. No results are passed back to the PL/SQL.
Writing "SELECT * FROM a_table" is not that hard and much safer.
I use a cursor for the statement:
SELECT NAME FROM STUDENT WHERE ROLL = 1;
I used:
CURSOR C IS SELECT NAME FROM STUDENT WHERE ROLL = roll;
--roll is a variable I receive via a procedure, and the procedure works fine for the received parameter.
Upon executing this, I am able to retrieve all records with roll = 1.
Now, I need to retrieve the records of a group (possibly via a cursor), just like:
SELECT NAME FROM STUDENT WHERE ROLL IN (2, 4, 6);
But the values in the IN clause are known only at run time. How should I do this? That is, is there any way I could assign parameters to the WHERE clause of the cursor?
I tried using an array in the declaration of the cursor, but an error pops up telling something like: standard types cannot be used.
I used:
CURSOR C IS SELECT NAME FROM STUDENT WHERE ROLL IN (rolls);
--rolls is an array initialized with the required roll numbers.
First, I assume that the parameter to your procedure doesn't actually match the name of a column in the STUDENT table. If you actually coded the statement you posted, roll would be resolved as the name of the column, not the parameter or local variable so this statement would return every row in the STUDENT table where the ROLL column was NOT NULL.
CURSOR C
IS SELECT NAME
FROM STUDENT
WHERE ROLL = roll;
Second, while it is possible to use dynamic SQL as #Gaurav Soni suggests, doing so generates a bunch of non-sharable SQL statements. That's going to flood the shared pool, probably aging other statements out of cache, and use a lot of CPU hard-parsing the statement every time. Oracle is built on the premise that you are going to parse a SQL statement once, generally using bind variables, and then execute the statement many times with different values for the bind variables. Oracle can go through the process of parsing the query, generating the query plan, placing the query in the shared pool, etc. only once and then reuse all that when you execute the query again. If you generate a bunch of SQL statements that will never be used again because you're using dynamic SQL without bind variables, Oracle is going to end up spending a lot of time caching SQL statements that will never be executed again, pushing useful cached statements that will be used again out of the shared pool meaning that you're going to have to re-parse those queries the next time they're encountered.
Additionally, you've opened yourself up to SQL injection attacks. An attacker can exploit the procedure to read any data from any table or execute any function that the owner of the stored procedure has access to. That is going to be a major security hole even if your application isn't particularly security conscious.
You would be better off using a collection. That prevents SQL injection attacks and it generates a single sharable SQL statement so you don't have to do constant hard parses.
SQL> create type empno_tbl is table of number;
2 /
Type created.
SQL> create or replace procedure get_emps( p_empno_arr in empno_tbl )
2 is
3 begin
4 for e in (select *
5 from emp
6 where empno in (select column_value
7 from table( p_empno_arr )))
8 loop
9 dbms_output.put_line( e.ename );
10 end loop;
11 end;
12 /
Procedure created.
SQL> set serveroutput on;
SQL> begin
2 get_emps( empno_tbl( 7369,7499,7934 ));
3 end;
4 /
SMITH
ALLEN
MILLER
PL/SQL procedure successfully completed.
create or replace procedure dynamic_cur(p_empno VARCHAR2) IS
cur sys_refcursor;
v_ename emp.ename%type;
begin
open cur for 'select ename from emp where empno in (' || p_empno || ')';
loop
fetch cur into v_ename;
exit when cur%notfound;
dbms_output.put_line(v_ename);
end loop;
close cur;
end dynamic_cur;
Procedure created
Run the procedure dynamic_cur
declare
v_empno varchar2(200) := '7499,7521,7566';
begin
dynamic_cur(v_empno);
end;
Output
ALLEN
WARD
JONES
Note:As mentioned by XQbert,dynamic cursor leads to SQL injection ,but if you're not working on any critical requirement ,where security is not involved then you can use this .
Maybe you can pass rolls as a set of quoted comma separated values.
e.g. '1', '2' etc
If this value is passes into the procedure in a varchar input variable, the it can be used to get multiple rows as per the table match.
Hence the cursor
SELECT NAME FROM STUDENT WHERE ROLL IN (rolls);
will be evaluated as
SELECT NAME FROM STUDENT WHERE ROLL IN ('1','2');
Hope it helps
I'm attempting to write a simple query where I declare some variables and then use them in a select statement in Oracle. I've been able to do this before in SQL Server with the following:
DECLARE #date1 DATETIME
SET #date1 = '03-AUG-2010'
SELECT U.VisualID
FROM Usage u WITH(NOLOCK)
WHERE U.UseTime > #Date1
From the searching I've done it appears you can not declare and set variables like this in Select statements. Is this right or am I mssing something?
From the searching I've done it appears you can not declare and set variables like this in Select statements. Is this right or am I missing something?
Within Oracle PL/SQL and SQL are two separate languages with two separate engines. You can embed SQL DML within PL/SQL, and that will get you variables. Such as the following anonymous PL/SQL block. Note the / at the end is not part of PL/SQL, but tells SQL*Plus to send the preceding block.
declare
v_Date1 date := to_date('03-AUG-2010', 'DD-Mon-YYYY');
v_Count number;
begin
select count(*) into v_Count
from Usage
where UseTime > v_Date1;
dbms_output.put_line(v_Count);
end;
/
The problem is that a block that is equivalent to your T-SQL code will not work:
SQL> declare
2 v_Date1 date := to_date('03-AUG-2010', 'DD-Mon-YYYY');
3 begin
4 select VisualId
5 from Usage
6 where UseTime > v_Date1;
7 end;
8 /
select VisualId
*
ERROR at line 4:
ORA-06550: line 4, column 5:
PLS-00428: an INTO clause is expected in this SELECT statement
To pass the results of a query out of an PL/SQL, either an anonymous block, stored procedure or stored function, a cursor must be declared, opened and then returned to the calling program. (Beyond the scope of answering this question. EDIT: see Get resultset from oracle stored procedure)
The client tool that connects to the database may have it's own bind variables. In SQL*Plus:
SQL> -- SQL*Plus does not all date type in this context
SQL> -- So using varchar2 to hold text
SQL> variable v_Date1 varchar2(20)
SQL>
SQL> -- use PL/SQL to set the value of the bind variable
SQL> exec :v_Date1 := '02-Aug-2010';
PL/SQL procedure successfully completed.
SQL> -- Converting to a date, since the variable is not yet a date.
SQL> -- Note the use of colon, this tells SQL*Plus that v_Date1
SQL> -- is a bind variable.
SQL> select VisualId
2 from Usage
3 where UseTime > to_char(:v_Date1, 'DD-Mon-YYYY');
no rows selected
Note the above is in SQLPlus, may not (probably won't) work in Toad PL/SQL developer, etc. The lines starting with variable and exec are SQLPlus commands. They are not SQL or PL/SQL commands. No rows selected because the table is empty.
I have tried this and it worked:
define PROPp_START_DT = TO_DATE('01-SEP-1999')
select * from proposal where prop_start_dt = &PROPp_START_DT
The SET command is TSQL specific - here's the PLSQL equivalent to what you posted:
v_date1 DATE := TO_DATE('03-AUG-2010', 'DD-MON-YYYY');
SELECT u.visualid
FROM USAGE u
WHERE u.usetime > v_date1;
There's also no need for prefixing variables with "#"; I tend to prefix variables with "v_" to distinguish between variables & columns/etc.
See this thread about the Oracle equivalent of NOLOCK...
Try the to_date function.
Coming from SQL Server as well, and this really bugged me. For those using Toad Data Point or Toad for Oracle, it's extremely simple. Just putting a colon in front of your variable name will prompt Toad to open a dialog where you enter the value on execute.
SELECT * FROM some_table WHERE some_column = :var_name;
I have a fairly complex query that will be referencing a single date as a start or stop date multiple times throughout. I'm going to have to run this query for 3 different fiscal years, and don't want to have to hunt down the date 17 times in order to change it throughout my query.
Is there a way to set a variable at the beginning of my query and reference it throughout? I'm not looking to write a whole function, just reference a variable throughout my query.
Yes, depends how you want to do it.
You could use an anonymous procedure IE:
BEGIN
v_date DATE := TO_DATE(your_date, your_date_mask);
[your query referencing v_date where ever you need];
END;
Or if you run the query in SQLPlus, you use & to note variables (IE: &your_date), and will be prompted for the value when you run the script.
As OMG Ponies says, inside PL/SQL you can always refer to any PL/SQL variable (including parameters) right in the SQL as long as it's static SQL. Outside PL/SQL, or if your SQL is dynamic (because native dynamic SQL doesn't support reusable named parameters at least as of 10g) you can use the following trick. Add the following before the WHERE clause in your query:
CROSS JOIN (SELECT :dateparam Mydate FROM dual) Dateview
And everywhere you want to refer to that value in your main query, call it Dateview.Mydate Then when you execute the query, you need only pass in the one bind parameter.
You're not really saying how you reference this so I'll just show from SQL*Plus point of view.
Two ways
Have it prompt you for the value. Since you use the same variable many times you'll want to use the && operator.
SQL> SELECT &&var, &&var FROM Dual;
Enter value for var: 'PUMPKIN'
old 1: SELECT &&var, &&var FROM Dual
new 1: SELECT 'PUMPKIN', 'PUMPKIN' FROM Dual
'PUMPKI 'PUMPKI
------- -------
PUMPKIN PUMPKIN
Alternatively you could set it before you ran your SQL.
SQL> VARIABLE new_var VARCHAR2(20);
SQL> EXECUTE :new_var := 'PUMPKIN PIE';
PL/SQL procedure successfully completed.
SQL> SELECT :new_var, :new_var FROM DUAL;
:NEW_VAR :NEW_VAR
-------------------------------- --------------------------------
PUMPKIN PIE PUMPKIN PIE
If you use Toad with second mouse button -> Execute as Script, so not prompt you for values:
var myVar varchar2(20);
exec :req := 'x';
delete from MYTable where Field =
:myVar;