I'm having some trouble truncating some tables that get generated in my base.
The table names get saved and I can do it manually, but I wanted to see if it could be automated until its fixed.
What I've done so far is get all the table names and a id/number into my own help table. My errors begin around the loop/Execute immediate where im not sure how to use the data I've gotten in the syntax and i cant find any similar examples.
create table HlpTruncTable as SELECT SUBSTR(argument, 3) as tblName, rownum as Nr
FROM tblLogHlp
WHERE status = 'E' and argument like '0,awfh%' and LAST_UPDATE <= ADD_MONTHS(sysdate,-1);
for i in 1..(select max(nr) from HlpTruncTable) LOOP
execute immediate TRUNCATE TABLE (select tblName from HlpTruncTable where nr = (i));
END LOOP;
drop table hlpTruncTable;
I would do it like this:
declare
cursor HlpTruncTable is
SELECT SUBSTR(argument, 3) as tblName
FROM tblLogHlp
WHERE status = 'E' and argument like '0,awfh%' and LAST_UPDATE <= ADD_MONTHS(sysdate,-1);
BEGIN
FOR aTable IN HlpTruncTable LOOP
execute immediate 'TRUNCATE TABLE '||aTable.tblName;
END LOOP;
END;
Related
I know create table as select * from table (CTA)S works for 1 table here but, I need to CTAS 1-100 tables in a single command with no data,Can someone help here to give a script that works in ATHENA.
I tried a for loop that works with oracle but here in Athena it doesnt work as single statement
begin
for idx in 1..100 loop
execute immediate
'Create table test'|| idx ||' AS
Select *
FROM test2 WITH NO DATA'
end loop;
end;
I have a problem by creating a Procdure with a specific WITH clause. I use an Oracle database. I need a temp table for mapping specific values during time of execution.
In addition I have the following Oracle procedure. This Procedure will be created and executed by bringing into database:
How can I create this kind of Oracle SQL Procedure? Many thanks for helping me!
Use your WITH clause in a cursor FOR loop in your procedure:
DECLARE
PROCEDURE myProcedure(pinSchema IN VARCHAR2) AS
BEGIN
FOR aRow IN (WITH t AS (SELECT 'myFirstOldSchema' AS OLD_SCHEMA,
'myFirstNewSchema' AS NEW_SCHEMA
FROM DUAL UNION ALL
SELECT 'mySecondOldSchema' AS OLD_SCHEMA,
'mySecondNewSchema' AS NEW_SCHEMA
FROM DUAL UNION ALL
SELECT 'myThirdOldSchema' AS OLD_SCHEMA,
'myThirdNewSchema' AS NEW_SCHEMA
FROM DUAL)
SELECT t.*
FROM t
WHERE t.OLD_SCHEMA = pinSchema)
LOOP
-- Here a specific value from column "OLD_SCHEMA" must be inserted
EXECUTE IMMEDIATE 'INSERT INTO ' || aRow.OLD_SCHEMA ||
'.myTable(column_1, column_2, column_3)
(SELECT extern_column_1,
extern_column_2,
extern_column_3
FROM ' || aRow.NEW_SCHEMA || '.myExternTable)';
END LOOP;
END myProcedure;
BEGIN
FOR S IN (SELECT * FROM ROOT_SCHEMA.myTableWithSchema)
LOOP
-- First loop S.mySchemata represent the value 'myFirstOldSchema'
-- Second loop S.mySchemata represent the value 'mySecondOldSchema'
-- Third loop S.mySchemata represent the value 'myThirdOldSchema'
myProcedure(S.mySchemata);
END LOOP
COMMIT;
END;
Not tested on animals - you'll be first!
I have a question regarding ORACLE, I wrote a PLSQL CODE that checks if a table exists, if it exists then I select something from this table..pseudocode is like:
if (table exists)
Select from table where....
the problem is that I always get an error if the table does not exist, even if the if condition is never met and the select statement is never executed.
I think it is because my code is checked at compile time: "select from.." and then it prints an error if the table does not exist. How can I solve such an issue?.. here is how my code looks like (I used generic names):
DECLARE
v_table_exists NUMBER;
BEGIN
SELECT NVL(MAX(1), 0)
INTO v_table_exists
FROM ALL_TABLES
WHERE TABLE_NAME = 'TABLE_TEST';
IF v_table_exists = 1 THEN
INSERT INTO MY_TABLE(COLUMN1, COLUMN2, COLUMN3, COLUMN4)
SELECT 1234,
5678,
T.COLUMN_TEST1,
T.COLUMN_TEST2
FROM TABLE_TEST T
WHERE T.FLAG = 1;
END IF;
END;
The issue is exactly in the fact that your procedure con not be compiled as it refers to a non existing object; you may need some dynamic SQL for this; for example:
create or replace procedure checkTable is
vCheckExists number;
vNum number;
begin
-- check if the table exists
select count(1)
into vCheckExists
from user_tables
where table_name = 'NON_EXISTING_TABLE';
--
if vCheckExists = 1 then
-- query the table with dynamic SQL
execute immediate 'select count(1) from NON_EXISTING_TABLE'
into vNum;
else
vNum := -1;
end if;
dbms_output.put_line(vNum);
end;
The procedure compiles even if the table does not exist; if you call it now, you get:
SQL> select count(1) from NON_EXISTING_TABLE;
select count(1) from NON_EXISTING_TABLE
*
ERROR at line 1:
ORA-00942: table or view does not exist
SQL> exec checkTable;
-1
PL/SQL procedure successfully completed.
Then, if you create the table and call the procedure again:
SQL> create table NON_EXISTING_TABLE(a) as select 1 from dual;
Table created.
SQL> exec checkTable;
1
PL/SQL procedure successfully completed.
The same way I showed a SELECT, you can do an UPDATE or whatever SQL query you need; if you do something different from a SELECT, the INTO clause has to be removed.
For example, say you need to insert into a different table, the above code should be edited this way:
if vCheckExists = 1 then
execute immediate 'insert into target(a, b, c) select a, 1, 100 from NON_EXISTING_TABLE';
end if;
Everything will need to be done in Dynamic SQL (DBMS_SQL) or EXECUTE_IMMEDIATE otherwise your code will never compile (or package will be invalided) if table does not exists.
DBMS_SQL Example
EXECUTE_IMMEDIATE Example
According to this article, in Oracle Database Server static SQL is indeed checked at compile time to ensure referenced objects exist.
So I advise you to use dynamic SQL instead of static SQL, through a varchar for example.
I have a table that store the name of other tables. Like
COL_TAB
--------------
TABLE_NAME
--------------
TAB1
TAB2
TAB3
What i want to do is that, i want to run a sql query on table like this,
SELECT * FROM (SELECT TABLE_NAME from COL_TAB WHERE TABLE_NAME = 'TAB1')
Thanks
An Oracle SQL query can use a dynamic table name, using Oracle Data Cartridge and the ANY* types. But before you use those advanced features, take a step back and ask yourself if this is really necessary.
Do you really need a SQL statement to be that dynamic? Normally this is better handled by an application that can submit different types of queries. There are many application programming languages and toolkits that can handle unexpected types. If this is for a database-only operation, then normally the results are stored somewhere, in which case PL/SQL and dynamic SQL are much easier.
If you're sure you've got one of those rare cases that needs a totally dynamic SQL statement, you'll need something like my open source project Method4. Download and install it and try the below code.
Schema Setup
create table tab1(a number);
create table tab2(b number);
create table tab3(c number);
insert into tab1 values(10);
insert into tab2 values(20);
insert into tab3 values(30);
create table col_tab(table_name varchar2(30), id number);
insert into col_tab values('TAB1', 1);
insert into col_tab values('TAB1', 2);
insert into col_tab values('TAB1', 3);
commit;
Query
select * from table(method4.dynamic_query(
q'[
select 'select * from '||table_name sql
from col_tab
where id = 1
]'));
Result:
A
--
10
You'll quickly discover that queries within queries are incredibly difficult. There's likely a much easier way to do this, but it may require a design change.
I don't have a database by hand to test this but I think you are looking for something like this:
DECLARE
-- Create a cursor on the table you are looking through.
CURSOR curTable IS
SELECT *
FROM MainTable;
recTable curTable%ROWTYPE;
vcQuery VARCHAR2(100);
BEGIN
-- Loop through all rows of MainTable.
OPEN curTable;
LOOP
FETCH curTable INTO recTable;
EXIT WHEN curTable%NOTFOUND;
-- Set up a dynamic query, with a WHERE example.
vcQuery := 'SELECT ColumnA, ColumnB FROM ' || recTable.Table_Name || ' WHERE 1 = 1';
-- Execute the query.
OPEN :dyn_cur FOR vcQuery;
END LOOP;
CLOSE curTable;
END;
/
Try this
CREATE OR REPLACE PROCEDURE TEST IS
sql_stmt VARCHAR2(200);
V_NAME VARCHAR2(20);
BEGIN
sql_stmt := 'SELECT * FROM ';
EXECUTE IMMEDIATE sql_stmt|| V_NAME;
END;
Update
select statement dont work in procedure.
in sql server you can try sql block
Declare #name varchar2(50)
Select #name='Select * from '+TABLE_NAME from COL_TAB WHERE TABLE_NAME = 'TAB1'
EXEC(#name);
I would like to create a script pl/sql where I can modify the value of my column ROW_NUMBER (the first time the value of ROW_NUMBER equal NULL).
This is the structure of my table 'A' :
CREATE TABLE A
(
"NAME" VARCHAR2(25 BYTE),
"NUM" NUMBER(10,0)
)
I would like to foreach all rows of table A and increment my Column 'NUM' by 1 if Column 'NAME' equal 'DEB'.
I would like to get the result like :
I created one pl/sql script :
DECLARE
INcrmt NUMBER(4):=1;
line WORK_ODI.TEST_SEQ%ROWTYPE;--before fetch it returns 0
CURSOR c_select IS
SELECT ROW_NUMBER,VALUE FROM WORK_ODI.TEST_SEQ;
BEGIN
OPEN c_select;
LOOP
FETCH c_select INTO line;
DBMS_OUTPUT.PUT_LINE(line.VALUE);
if line.VALUE like '%DEB%'
then
UPDATE WORK_ODI.TEST_SEQ SET ROW_NUMBER = INcrmt WHERE VALUE=line.VALUE;
INcrmt := INcrmt + 1;
end if;
if line.VALUE not like '%DEB%'
then
UPDATE WORK_ODI.TEST_SEQ SET ROW_NUMBER = INcrmt WHERE VALUE=line.VALUE;
end if;
EXIT WHEN c_select%NOTFOUND;
END LOOP;
CLOSE c_select;
COMMIT;
END;
DECLARE
INcrmt NUMBER(4):=1;
line WORK_ODI.TEST_SEQ%ROWTYPE;--before fetch it returns 0
CURSOR c_select IS
SELECT ROW_NUMBER,VALUE FROM WORK_ODI.TEST_SEQ;
BEGIN
OPEN c_select;
LOOP
FETCH c_select INTO line;
DBMS_OUTPUT.PUT_LINE(line.VALUE);
if line.VALUE like '%DEB%'
then
UPDATE WORK_ODI.TEST_SEQ SET ROW_NUMBER = INcrmt WHERE VALUE=line.VALUE;
INcrmt := INcrmt + 1;
end if;
if line.VALUE not like '%DEB%'
then
UPDATE WORK_ODI.TEST_SEQ SET ROW_NUMBER = INcrmt WHERE VALUE=line.VALUE;
end if;
EXIT WHEN c_select%NOTFOUND;
END LOOP;
CLOSE c_select;
COMMIT;
END;
but this is not work well , please take a look at what it gives me as result :
please anybody can help me
First, you should have an Aid column of some sort. In Oracle 12+, you can use an identity. In earlier versions, you can use a sequence. This provides an ordering for the rows in the table, based on insert order.
Second, you can do what you want on output:
select a.*,
sum(case when a.name like 'DEB%' then 1 else 0 end) over (order by aid) as row_number
from a;
If you really need to keep the values in the table, then you can use a merge statement to assign values to existing rows (the aid column is very handy for this). You will need a trigger afterwards to maintain it.
My suggestion is to do the calculation on the data, rather than storing the value in the data. Maintaining the values with updates and deletes seems like a real pain.