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
Related
I am trying to derive a table with counts from multiple tables. The tables are not on my schema. The table names on the schema that I am interested in all start with 'STAF_' and end with '_TS'. The criteria i am looking for is where SEP = 'MO'. So for example, the query in its base form is:
select area, count(SEP) areacount
from mous.STAF_0001_TS
where SEP = 'MO'
group by area;
I have about 1000 tables that i'd like to do this for.
Ultimatly, I'd like the output to be a table on my schema that looks like the following:
area| areacount
0001| 3
0002| 7
0003| 438
Thank you.
As a first step I'd write an SQL query that generates an SQL query:
SELECT 'SELECT area, count(*) FROM '||c.table_name||'UNION ALL' as run_me
FROM all_tables c
WHERE c.table_name LIKE 'STAF\_%\_MS' escape '\'
Running this will produce an output that is another SQL query. Copy the result text out of your results grid and paste it back into your query pane. Delete the final UNION ALL and run it
Once you dig how to write an SQL query that generate an SQL query, you can look at turning it into a view, or creating a dynamic query in a string.
Gotta say, this is a horrible way to store data; you'd be better off using ONE table with an extra column containing whatever is in xxx of STAF_xxx_MS right now
In Oracle 12c, you can embed a FUNCTION that will query the number of rows in any given table. Then you can use that function in your main query. Here is an example:
WITH FUNCTION cnt ( p_owner VARCHAR2, p_table_name VARCHAR2 ) RETURN NUMBER IS
l_cnt NUMBER;
BEGIN
EXECUTE IMMEDIATE 'SELECT count(*) INTO :cnt FROM ' || p_owner || '.' || p_table_name INTO l_cnt;
RETURN l_cnt;
EXCEPTION WHEN OTHERS THEN
RETURN NULL; -- This will happen for entries in ALL_TABLES that are not directly accessible (e.g., IOT overflow tables)
END cnt;
SELECT t.owner, t.table_name, cnt(t.owner, t.table_name)
FROM all_tables t
where t.table_Name like 'STAF\_%\_MS' escape '\';
I am trying to find how many occurrences of a particular value there are in a particular column in an Oracle database. The column is used in dozens of tables and I'm going to have to run the queries many times, so I don't want to query each table individually. I can get a list of the tables to search with something like:
Select table_name from all_tab_cols
join all_tables using (table_name)
where column_name = 'EmployeeId' and num_rows > 0
The next step is to iterate through that list of table names and output each table that contains a particular value in the EmployeeId column. For example, output might be something like:
**Table Name Column_name # Rows for EmployeeId = '123456'**
Table 1 EmployeeId 1
Table 2 EmployeeId 12
etc.
I'm not a developer and don't have experience using cursors in SQL scripts, so any help would be greatly appreciated.
try using CURSOR FOR LOOP.
Probably it may look as shown below (not tried).
BEGIN
FOR item IN
(Select table_name,column_name,num_rows from all_tab_cols
join all_tables using (table_name)
where column_name = 'EmployeeId' and num_rows > 0)
LOOP
DBMS_OUTPUT.PUT_LINE
(item.table_name || ' ' || item.column_name ||' '||item.num_rows);
END LOOP;
END;
Our company is using Oracle 11g (11.2.0.5.0)
I'm looking for a way to execute external query (in this specific example called from PHP website) that would FOR LOOP through set of data and return results in the form of table (like normal SELECT would)
USERS table:
DB1
DB2
DB3
...
DBO
Each user's schema contains ITEM table:
ID CODE TYPE
--------------------
1 0001 A
2 0043 A
3 00A5 V
...
I want to execute a query that would loop through all USERS and fetch data from their ITEM tables, something along lines of my not working
FOR user IN (SELECT * FROM all_users)
LOOP
SELECT CODE, user FROM user.ITEM_TABLE WHERE TYPE = 'V'
END LOOP;
That would return
CODE USER
-------------
00A5 DB1
0434 DB2
0999 DB2
...
If I correctly understand your need, maybe this can help:
declare
type tabUser is table of varchar2(30);
type tabCode is table of varchar2(30);
vTabCode tabCode;
vTabUser tabUser;
vSQL varchar2(32767);
begin
select listagg('select code, ''' || owner || ''' from ' || owner || '.item_table where type = ''V''', ' UNION ALL ')
within group (order by owner)
into vSQL
from dba_tables where table_name = 'ITEM_TABLE';
--
dbms_output.put_line(vSQL);
--
execute immediate vSQl bulk collect into vTabCode, vTabUser;
--
/* ... what you need to do with your data */
end;
/
I removed all_users, given that probably there are users that do not have the ITEM_TABLE table, for example SYS; in this way you only query for really existing tables.
The first part dynamically builds the query you need, by concatenating queries from different users; in the second part you have your data extracted from all the tables, so you can do whatever you need.
I have a problem in that I want my output to be a single table (lets call it Output) with 2 columns: one for the "TableName" and one for the DateTime of the last update (using the scn_to_timestamp(max(ora_rowscn)) command).
I have 100 tables and I want to pull in the last update date/times for all these tables into the Output table.
So I can do this:
insert into Output(TableName)
select table_name
from all_tables;
which will put all the tables I have from my database into the TableName column. But I don't know how to loop through each entry and use the tablename as a variable and pass this into the scn_to_timestamp(ora_rowscn).
I thought I would try something like below:
for counter in Output(TableName) LOOP
insert into Output(UpdateDate)
select scn_to_timestamp(max(ora_rowscn))
from counter;
END LOOP;
Any suggestions?
Thank you
This query is a little bit clumsy as it uses xmlgen to execute dynamic sql in a query, but it might work for you.
select x.*
from all_tables t,
xmltable('/ROWSET/ROW' passing
dbms_xmlgen.getxmltype('select ''' || t.table_name ||
''' tab_name, max(ora_rowscn) as la from ' ||
t.table_name)
COLUMNS tab_name varchar2(30) PATH 'TAB_NAME',
max_scn number PATH 'LA') x
Here is a sqlfiddle demo
You can also use PLSQL and then use execute immediate
I have the following table name template, there are a couple with the same name and a number at the end: fmj.backup_semaforo_geo_THENUMBER, for example:
select * from fmj.backup_semaforo_geo_06391442
select * from fmj.backup_semaforo_geo_06398164
...
Lets say I need to select a column from every table which succeeds with the 'fmj.backup_semaforo_geo_%' filter, I tried this:
SELECT calle --This column is from the backup_semaforo_geo_# tables
FROM (SELECT table_name
FROM all_tables
WHERE owner = 'FMJ' AND table_name LIKE 'BACKUP_SEMAFORO_GEO_%');
But I'm getting the all_tables tables name data:
TABLE_NAME
----------
BACKUP_SEMAFORO_GEO_06391442
BACKUP_SEMAFORO_GEO_06398164
...
How can I achieve that without getting the all_tables output?
Thanks.
Presumably your current query is getting ORA-00904: "CALLE": invalid identifier, because the subquery doesn't have a column called CALLE. You can't provide a table name to a query at runtime like that, unfortunately, and have to resort to dynamic SQL.
Something like this will loop through all the tables and for each one will get all the values of CALLE from each one, which you can then loop through. I've used DBMS_OUTPUT to display them, assuming you're doing this in SQL*Plus or something that can deal with that; but you may want to do something else with them.
set serveroutput on
declare
-- declare a local collection type we can use for bulk collect; use any table
-- that has the column, or if there isn't a stable one use the actual data
-- type, varchar2(30) or whatever is appropriate
type t_values is table of table.calle%type;
-- declare an instance of that type
l_values t_values;
-- declare a cursor to generate the dynamic SQL; where this is done is a
-- matter of taste (can use 'open x for select ...', then fetch, etc.)
-- If you run the query on its own you'll see the individual selects from
-- all the tables
cursor c1 is
select table_name,
'select calle from ' || owner ||'.'|| table_name as query
from all_tables
where owner = 'FMJ'
and table_name like 'BACKUP_SEMAFORO_GEO%'
order by table_name;
begin
-- loop around all the dynamic queries from the cursor
for r1 in c1 loop
-- for each one, execute it as dynamic SQL, with a bulk collect into
-- the collection type created above
execute immediate r1.query bulk collect into l_values;
-- loop around all the elements in the collection, and print each one
for i in 1..l_values.count loop
dbms_output.put_line(r1.table_name ||': ' || l_values(i));
end loop;
end loop;
end;
/
May be a dynamic SQL in a PLSQL program;
for a in (SELECT table_name
FROM all_tables
WHERE owner = 'FMJ' AND table_name LIKE 'BACKUP_SEMAFORO_GEO_%')
LOOP
sql_stmt := ' SELECT calle FROM' || a.table_name;
EXECUTE IMMEDIATE sql_stmt;
...
...
END LOOP;