PLSQL oracle select after declare ORA-06550 PLS-00103 - sql

Question

Using PL/SQL Developer client.
Oracle throws me ORA-065550 PLS-00103 Encountered the symbol "SELECT".
Well, can not find what's wrong here.
DECLARE someId NUMBER;
BEGIN
select id into someId from someTable where someColumn = 'someUniqueValue';
select * from someTable; --here
END;
select * from someTable; --or here
Neither second select, neither third works. When I dmbs_output someId into console it works well, this assigning to declared variable. But why I can not just select after 'into'? I want to declare one time value, and then make
select * from someTable where id = someId
or to be precised want to make like thousand inserts and I want to cache that first select.
DECLARE someId NUMBER;
BEGIN
select id into someId from someTable where someColumn = 'someValue';
END;
/
select * from otherTable where otherTableId = someId;
Here I lost someId scope I guess.

Answer 1

Basically you doing a lot of mistakes while doing this code.
1.You cant just 'SELECT *' in the anonymous block. You need to have cursor to do it.
2.Your variable scope is till the anonymous block. Now you are trying to access the variable outside the block --> NAAH not possible.
So I have tried to resolve your issue by below snippet hope it helps.
DECLARE
someId NUMBER;
p_lst sys_refcursor;
BEGIN
SELECT id INTO someId FROM someTable WHERE someColumn = 'someUniqueValue';
OPEN p_lst FOR
'SELECT * FROM someTable
where otherTableId = '||someId;
END;

Answer 2

Assuming you're coding a sql script, you can
1) declare your variable
2) populate it in an anonymous pl/sql block
3) use it elsewhere
--1
variable my_num number
--2
begin
select 1 into :my_num from dual;
end;
/
--3
select :my_num from dual;

Answer 3

That you can achieve through using SQL*Plus
SQL> variable id number
SQL> begin
select 1000 into :id from dual;
end;
/
SQL> print id
ID
----------
1000
SQL> SELECT * FROM tbl_a WHERE id = :id
In Oracle doesn't let you implicitly return the result of a query. The result always has to be explicitly returned in some fashion. The simplest way is to use DBMS_OUTPUT (roughly equivalent to print) to output the variable:
DECLARE
myname varchar2(20);
BEGIN
myname := 'Tom';
dbms_output.print_line(myname);
END;
This isn't terribly helpful if you're trying to return a result set, however. In that case, you'll either want to return a collection or a refcursor. However, using either of those solutions would require wrapping your code in a function or procedure and running the function/procedure from something that's capable of consuming the results. A function that worked in this way might look something like this:
CREATE FUNCTION my_function (myname in varchar2)
my_refcursor out sys_refcursor
BEGIN
open my_refcursor for
SELECT *
FROM Customers
WHERE Name = myname;
return my_refcursor;
END my_function;