I want to get data from table which name is keeping in another table. Trying to get this as described below leads to getting result from nested SELECT only
select * from (select value from ex_scheme.ex_tab where name = 'ex_name.current_table_name')
I mean, I've got equivalent result as from just
select value from ex_scheme.ex_tab where name = 'ex_name.current_table_name'
query.
UPDATED
Ok, lets double-check if I was correctly understood.
I have to see one table data (lets call this table "table1"). I need to know this table name. And I know where its name is keeping. It is in another table (call it "names_table") in column "name" (row with column value = 'table1'). And I can get it by query
select name from names_table where value = 'table1'
If you know in advance the column and its type, you can build some dynamic SQL to dynamically query a table or another.
For example, say you have tables like the following:
create table table1(col) as (select 1 from dual);
create table table2(col) as (select 2 from dual);
create table tab_of_tabs (tab_name) as (select 'TABLE1' from dual);
You can use dynamic SQL to build a query that scans a table whose name is the result of a query:
SQL> declare
2 vSQL varchar2(1000);
3 vResult number;
4 begin
5 select 'select sum(col) from ' || tab_name -- build the query
6 into vSQL
7 from tab_of_tabs;
8 --
9 execute immediate vSQL into vResult; -- run the query
10 --
11 dbms_output.put_line('Result: ' || vResult);
12 end;
13 /
Result: 1
PL/SQL procedure successfully completed.
SQL>
If I understand correctly, you could use a nested query in a where clause. For example,
select * from table1 where table1.name in (select name from table2);
This assumes there's a column "name" in table1. The result of this query should return the rows in table1 that are in table2.
try giving alias
select n.* from (select value from ex_scheme.ex_tab where name = 'ex_name.current_table_name') n;
Update:
It is in another table (call it "names_table") in column "name" (row
with column value = 'table1').
this query will work
select n.* from (select name from ex_scheme.ex_tab where name = 'ex_name.current_table_name') n;
sub query fetches name of table from another table .
Related
T_TABLE_N := UPPER(TABLE_N);
FOR ATTRIBUTE_ IN (SELECT HEADER_NAME FROM T_TABLE_N
GROUP BY HEADER_NAM )
Here, I use the T_TABLE_N table as a variable. But it wasn't taken as a table
How to solve this problem
I want to write a stored procedure that grabs all of the tables in a schema that have a column called "ID" , once I have those tables I want to output the counts of unique IDs within each table.
ex.
table1
table2
Output:
I have the latter portion implemented but the first part I'm having difficulties with. Here's my script so far:
create or replace PROCEDURE get_id_counts
IS
BEGIN
FOR table_n in (SELECT * FROM dba_tables) LOOP
EXECUTE IMMEDIATE 'SELECT ID, COUNT(*) FROM MySchema.' || table_n.table_name || ' GROUP BY ID';
END LOOP;
END;
/
execute get_id_counts;
Currently I receive the error : "%s: invalid identifier", I assume this is caused by the fact that not all of the tables in the schema have the column "ID"
Assuming that your database is Oracle
Use the dba_tab_columns to get only those which has ID column
So extend your query from
SELECT * FROM dba_tables
to
SELECT * FROM dba_tables where table_name in (select table_name from dba_tab_columns where column_name = 'ID');
I have a main table that has two columns with table names and id's. And I have those tables with table names in my DB.
For example, I find particular table name, selecting id. And then I want to populate table with that name with data. And I want to do that in one query. How I can do that?
The goal: to populate with data all tables at once, that has the names that similar with values in table name column from main table.
That is how I'm getting the list of tables. I should probably loop through it.
select tbl from asp_tbl where asp in (
select id from (
SELECT * FROM DIMENSION WHERE EXTERNALKEY LIKE 'W16%')
);
And then I will try to merge the data from other tables inside the table that needs to be populated:
MERGE INTO tbl d
USING
(SELECT ? nums, ? names from data_table) s
ON(d.product = s.product and d.ga = s.ga and d.metric_id = s.metric_id)
WHEN MATCHED THEN UPDATE SET d.names = s.names
WHEN NOT MATCHED THEN INSERT (nums, names)values(s.nums,s.names);
Did I provide enough info?
As I understand you need some stored procedure witch may fulfil a table with some test data. If so you may write something like:
create procedure fulfil_test_data (p_table_name varchar2) is
begin
for x IN (select tbl from asp_tbl where asp in (
SELECT table_id FROM DIMENSION WHERE EXTERNALKEY LIKE p_table_name )) loop
execute immediate 'insert into '|| x.tbl ||' (nums, names)
select level , chr(ascci(''A'') + mod(level,26)) from dual connect by level < 1001';
end loop;
end;
/
And call it
begin
fulfil_test_data('W16%');
end;
/
I am not sure if this is possible or not, but here is my problem with select expression in a sql loader file.
I have two tables.
TABLE 1
IDENTITYNUMBER
ID NUMBER
100 8
200 9
TABLE 2
TESTTABLE
NAME ID
John 100
data file for the loader sql
Jim,8
Carol,9
Now, I want to load this data in test table by replacing the second number with the id from the first table.
So this is how my test.ctl file looks like
load data
append
into table testtable
fields terminated by ',' optionally enclosed by '"'
(
NAME,
ID EXPRESSION "(select i.id from identitynumber i where i.number = :ID)"
)
But I keep getting this error:
SQL*Loader-291: Invalid bind variable ID in SQL string for column ID
I expect the table 2 to look like this after a successful execution of the loader script.
TESTTABLE
NAME ID
John 100
Jim 100
Carol 200
Any pointers will be greatly appreciated.
Do without "expression"
ID "(select i.id from identitynumber i where i.number = :ID)"
I don't think select's are allowed in sqlldr EXPRESSION
Functions are:
create function idtestfun(p_num in number) return number
is
l_num number;
begin
select id into l_num from identitynumber where "number"= p_num;
return l_num;
end;
and use it sqlldr config:
ID "idtestfun(:ID)"
Hi everyone what I'm wondering if I can do is create a table that lists the record counts of other tables. It would get those table names from a table. So let's assume I have the table TABLE_LIST that looks like this
name
---------
sports_products <-- contains 10 records
house_products <-- contains 8 records
beauty_products <-- contains 15 records
I would like to write a statement that pulls the names from those tables to query them and coount the records and ultimately produce this table
name numRecords
------------------------------
sports_products 10
house_products 8
beauty_products 15
So I think I would need to do something like this pseudo code
select *
from foreach tableName in select name from table_list
select count(*) as numRecords
from tableName
loop
You can have a function that is doing this for you via dynamic sql.
However, make sure to declare it as authid current_user. You do not want anyone to gain some sort of privilege elevation by exploiting your function.
create or replace function SampleFunction
(
owner in VarChar
,tableName in VarChar
) return integer authid current_user is
result Integer;
begin
execute immediate 'select count(*) from "' || owner || '"."' || tableName || '"'
INTO result;
return result;
end;
One option is to simply keep your DB statistics updated, use dbms_stats package or EM, and then
select num_rows
from all_tables
where table_name in (select name from table_list);
I think Robert Giesecke solution will work fine.
A more exotic way of solving this is by using dbms_xmlgen.getxml.
See for example: Identify a table with maximum rows in Oracle