I need to execute something like:
select
[very big SQL]
where phone_number in(:SQL2)
Is it possible to use bind variable for SQL2?
I want to save the execution plan of the major SQL.
Thanks.
Create a temporary table and save SQL2's results there prior to executing SQL1:
CREATE GLOBAL TEMPORARY TABLE mytemptable (id INT NOT NULL)
CREATE OUTLINE ol_sql1
ON
SELECT *
FROM sql1
WHERE id IN
(
SELECT id
FROM mytemptable
)
INSERT
INTO mytemptable
SELECT *
FROM sql2
SELECT *
FROM sql1
WHERE id IN
(
SELECT id
FROM mytemptable
)
If this query gets executed a lot of times, I wouldn't use a temporary table for it.
There is a 'trick' to bind an inlist, which Tom Kyte describes on his blog:
http://tkyte.blogspot.com/2006/06/varying-in-lists.html
I would bet on that being much more efficient. It should be easy to prove with a SQL Trace.
Further to Quassanoi's point. It sounds like you may not be familiar with temporary tables. This is a good introduction.
You only create the table once. Then within a given session you first:
populate the temporary table
execute your query pulling from the temporary table
rollback.
There's no risk of conflicting/overlapping with another session's data.
Related
I created a table in oracle like
CREATE TABLE suppliers AS (SELECT * FROM companies WHERE id > 1000);
I would like to know the complete select statement which was used to create this table.
I have already tried get_ddl but it is not giving the select statement. Can you please let me know how to get the select statement?
If you're lucky one of these statements will show the DDL used to generate the table:
select *
from gv$sql
where lower(sql_fulltext) like '%create table suppliers%';
select *
from dba_hist_sqltext
where lower(sql_text) like '%create table%';
I used the word lucky because GV$SQL will usually only have results for a few hours or days, until the data is purged from the shared pool. DBA_HIST_SQLTEXT will only help if you have AWR enabled, the statement was run in the last X days that AWR is configured to hold data (the default is 8), the statement was run after the last snapshot collection (by default it happens every hour), and the statement ran long enough for AWR to think it's worth saving.
And for each table Oracle does not always store the full SQL. For security reasons, DDL statements are often truncated in the data dictionary. Don't be surprised if the text suddenly cuts off after the first N characters.
And depending on how the SQL is called the case and space may be different. Use lower and lots of wildcards to increase the chance of finding the statement.
TRY THIS:
select distinct table_name
from
all_tab_columns where column_name in
(
select column_name from
all_tab_columns
where table_name ='SUPPLIERS'
)
you can find table which created from table
I have a query like this:
select PROMOTER_DSMID,
PROMOTER_NAME,
PROMOTER_MSISDN,
RETAILER_DSMID,
RETAILER_MSISDN,
RETAILER_NAME ,
ATTENDANCE_FLAG,
ATTENDANCE_DATE
from PROMO_ATTENDANCE_DETAILS
where PROMOTER_DSMID not in
(SELECT PROMOTER_DSMID
FROM PROMO_ATTENDANCE_DETAILS
WHERE PROMOTERS_ASM_DSMID='ASM123'
AND ATTENDANCE_FLAG='TRUE'
AND TRUNC(ATTENDANCE_DATE) ='16-07-17')
and PROMOTERS_ASM_DSMID='ASM123'
AND ATTENDANCE_FLAG='FALSE'
AND TRUNC(ATTENDANCE_DATE) ='16-07-17';
This query is taking too much time when I run this in PROD database because of large number of records.
I need to write a procedure for this but am not able to get the correct approach of how to write a procedure. Somebody please guide me.
"was thinking to write a proc in which inner select statement can put the data in some temporary table and then from that temporary table I can run the outer select statement"
No need for that. Use a WITH clause to select the data once and use it twice.
with cte as (
select PROMOTER_DSMID,
PROMOTER_NAME,
PROMOTER_MSISDN,
RETAILER_DSMID,
RETAILER_MSISDN,
RETAILER_NAME ,
ATTENDANCE_FLAG,
ATTENDANCE_DATE
from PROMO_ATTENDANCE_DETAILS
where PROMOTERS_ASM_DSMID='ASM123'
AND TRUNC(ATTENDANCE_DATE) ='16-07-17'
)
select *
from cte
where ATTENDANCE_FLAG='FALSE'
AND PROMOTER_DSMID not in
(SELECT PROMOTER_DSMID
FROM cte
where ATTENDANCE_FLAG='TRUE')
;
This will perform better than a temporary table, which involve a lot of disk I/O.
There are other possible performance improvements, depending on the usual tuning
considerations: data volume and skew, indexes, etc
I am using mybatis to perform a massive batch insert on an oracle DB.
My process is very simple: I am taking records from a list of files and inserting them into a specific table after performing some checks on the data.
-Each file contains an average of 180.000 records and I can have more than one file.
-Some records can be present in more than one file.
-A record is identical to another one if EVERY column matches, in other words I cannot simply perform a check on a specific field. And I have defined a constraint in my DB which makes sure this condition is satisfied.
To put it simply I want to just ignore the constraint exception Oracle will give to me in case that constraint is violated.
Record is not present?-->insert
Record is already present?--> go ahead
is this possible with mybatis?Or can I accomplish something at DB level?
I have control on both Application Server and DB so please tell me what's the most efficient way to accomplish this task (even though I'd like to avoid being too much DB dependant...)
of course, I'd like to avoid performing a select* before each insertion...given the number of records I am dealing with it would ruin my application's performances
Use the IGNORE_ROW_ON_DUPKEY_INDEX hint:
insert /*+ IGNORE_ROW_ON_DUPKEY_INDEX(table_name index_name) */
into table_name
select * ...
I'm not sure about JDBC, but at least in OCI it is possible. With batch operations you pass vectors as bind variables and you also get back vector(s) of returned IDs and also a vector of error codes.
You can also use MERGE on database server side together with custon collection types. Something like:
merge into t
using ( select * from TABLE(:var) v)
on ( v.id = t.id )
when not matched then insert ...
Where :var is bind variable of SQL type: TABLE OF <recordname>
The word "TABLE" is a construct used to cast from bind variable into a table.
Another option is to use SQL error loggin clause:
DBMS_ERRLOG.create_error_log (dml_table_name => 't');
insert into t(...) values(...) log errors reject limit unlimited;
Then after the load you will have to truncate error loging table err$_t;
another option would be to use external tables
It looks that any solution is quite a lot work to do, when compared to using sqlldr.
Ignore error with error table
insert
into table_name
select *
from selected_table
LOG ERRORS INTO SANJI.ERROR_LOG('some comment' )
REJECT LIMIT UNLIMITED;
and error table schema is :
CREATE GLOBAL TEMPORARY TABLE SANJI.ERROR_LOG (
ora_err_number$ number,
ora_err_mesg$ varchar2(2000),
ora_err_rowid$ rowid,
ora_err_optyp$ varchar2(2),
ora_err_tag$ varchar2(2000),
n1 varchar2(128)
)
ON COMMIT PRESERVE ROWS;
I want to check in Oracle that if is there any Procedure or trigger written on the database table which insert the records in the table.
Please help me to find out this because I have an existing table and want to check that in that table how records would be insert.
Thanks in advance!
Dependencies between objects are maintained in the system and can be read from DBA_DEPENDENCIES (or ALL_ or USER_DEPENDENCIES).
The only limitation is that dynamic statements (eg using execute immediate) are not included because they are not known at compile time.
Please use the below code snippet. Hope this helps!
SELECT *
FROM
(SELECT owner,
name,
type,
referenced_owner,
referenced_name,
referenced_type,
owner sdev_link_owner,
name sdev_link_name,
type sdev_link_type
FROM ALL_DEPENDENCIES
WHERE REFERENCED_OWNER = 'OBJECT_OWNER'
AND referenced_name = 'TABLE_NAME'
) sub1
ORDER BY 3 ASC;
We are trying to copy the current row of a table to mirror table by using a trigger before delete / update. Below is the working query
BEFORE UPDATE OR DELETE
ON CurrentTable FOR EACH ROW
BEGIN
INSERT INTO MirrorTable
( EMPFIRSTNAME,
EMPLASTNAME,
CELLNO,
SALARY
)
VALUES
( :old.EMPFIRSTNAME,
:old.EMPLASTNAME,
:old.CELLNO,
:old.SALARY
);
END;
But the problem is we have more than 50 coulmns in the current table and dont want to mention all those column names. Is there a way to select all coulmns like
:old.*
SELECT * INTO MirrorTable FROM CurrentTable
Any suggestions would be helpful.
Thanks,
Realistically, no. You'll need to list all the columns.
You could, of course, dynamically generate the trigger code pulling the column names from DBA_TAB_COLUMNS. But that is going to be dramatically more work than simply typing in 50 column names.
If your table happens to be an object table, :new would be an instance of that object so you could insert that. But it would be rather rare to have an object table.
If your 'current' and 'mirror' tables have EXACTLY the same structure you may be able to use something like
INSERT INTO MirrorTable
SELECT *
FROM CurrentTable
WHERE CurrentTable.primary_key_column = :old.primary_key_column
Honestly, I think that this is a poor choice and wouldn't do it, but it's a more-or-less free world and you're free (more or less :-) to make your own choices.
Share and enjoy.
For what it's worth, I've been writing the same stuff and used this to generate the code:
SQL> set pagesize 0
SQL> select ':old.'||COLUMN_NAME||',' from all_tab_columns where table_name='BIGTABLE' and owner='BOB';
:old.COL1,
:old.COL2,
:old.COL3,
:old.COL4,
:old.COL5,
...
If you feed all columns, no need to mention them twice (and you may use NULL for empty columns):
INSERT INTO bigtable VALUES (
:old.COL1,
:old.COL2,
:old.COL3,
:old.COL4,
:old.COL5,
NULL,
NULL);
people writing tables with that many columns should have no desserts ;-)