I have a table like this :
How can I sort it out in the form below :
Each set of records has been marked by a FlagID at end
Each set of records has been marked by a FlagID at end
I assume this means that each record is implicitly associated with the first non-null FlagID value that occurs at or after its position along the ID primary key. Thus, we can use a correlated subquery to project this implicit FlagID value for each record, sort by it, then sort by your Row column as tiebreaker for each set.
SELECT *
FROM YourTable T1
ORDER BY
(
SELECT TOP 1 T2.FlagID
FROM YourTable T2
WHERE T2.ID <= T1.ID
AND T2.FlagID IS NOT NULL
ORDER BY T2.ID DESC
),
T1.Row
However, if you're able to alter the database content, I would recommend you to explicitly populate all the FlagID fields, as this would make your life easier. If you do so, then the query becomes:
SELECT *
FROM YourTable T1
ORDER BY T1.FlagID,
T1.Row
Related
I am using Toad for oracle 12c. I need to copy a table and data (40M) from one shcema to another (prod to test). However there is an unique key(not the PK for this table) called record_Id col which has something data like this 3.000*******19E15. About 2M rows has same numbers(I believe its because very large number) which are unique in prod. When I try to copy it violets the unique key of that col. I am using toad "export data to another schema" function to copy the data.
when I execute query in prod
select count(*) from table_name
OR
select count(distinct(record_id) from table_name
Both query gives the exact same numbers of data.
I don't have DBA permission. How do I copy all data without violating unique key of the table.
Thanks in advance!
You can use UPSERT for decisional INSERT or UPDATE or you may write small procedure for this.
you may consider to use NOT EXISTS, but your data is big and it might not be resource efficient.
insert into prod_tab
select * from other_tab t1 where NOT exists (
select 1 from prod_tab t2 where t1.id = t2.id
);
In Oracle you can use a MERGE query for that.
The following query proceeds as follows for each data row :
if the source record_id does not yet exist in the target table, a new record is inserted
else, the existing record is updated with source values
For the sake of the example, I assumed that there are two other columns in the table : column1 and column2.
MERGE INTO target_table t1
USING (SELECT * from source_table t2)
ON (t1.record_id = t2.record_id)
WHEN MATCHED THEN UPDATE SET
t1.column1 = t2.column1,
t1.column2 = t2.column2
WHEN NOT MATCHED THEN INSERT
(record_id, column1, column2) VALUES (t2.record_id, t2.column1, t2.column2)
I have two partitoned tables on weekly interval called table1 and table2 and each table has columns like
SR_NO,
CARD_NUMBER,
TRANSACTION_DATE and
STATUS which contains only values like 'N' or 'P' or 'Y'.
I have created two indexes on both tables.
First one is normal local index on TRANSACTION_DATE and STATUS.
Second index is bitmap index on STATS.
I am comparing two tables like as shown in below select statement.
select a.sr_no, a.transacton_date, a.record_status
from table1 a inner join table2 b on a.card_number = b.card_number
and a.transaction_date = b.transaction_date
and a.Status = 'P'
and b.staus = 'P';
I am looping through above select satement data and updating STATUS column to 'Y' for matched data in table1 and updating 5000 records at a time using bulk insert concept and update statement is as follows i have used bind variables also in update statement.
update table1 set
status = 'Y'
where transaction_date = :date
and SR_NO = :SRNO
and STATUS = :status;
Bind varable assigned with select statement returned data.
Now my problem is above update statement is taking time then up on co ordination with our internal DBA team they suggested to drop bitmap indexes which slows down perfomance of DML statements.
I want to know is it true that bitmap indexes slows down performance of DML statements.
I have a table with a massive number of columns. So many, that when I do SELECT * I can't even see any values because all the columns fill up the screen. I'd like to do something like this:
SELECT * FROM my_table WHERE NAME LIKE '%unique name%' AND <THIS COLUMN> IS NOT NULL
Is this possible? Note: VALUE is not a column.
There are so many questions on SO that ask this same question, but they have some bizarre twist, and the actual question is not answered.
I've tried:
SELECT * FROM my_table WHERE NAME LIKE '%unique name%' AND VALUE NOT NULL
*
Invalid relational operator
SELECT * FROM my_table WHERE NAME LIKE '%unique name%' AND VALUE <> ''
*
'VALUE': invalid identifier
SELECT * FROM my_table WHERE NAME LIKE '%unique name%' AND COLUMN NOT NULL
*
Missing Expression
Bonus Questions:
Is there any way to force Oracle to only show one output screen at a time?
Is there a variable to use in the WHERE clause that relates to the current column? Such as: WHERE this.column = '1', where it would check each column to match that expression?
Is there any way to get back your last command in Oracle? (I have to remote into a Linux box running Oracle - it's all command line - can't even copy/paste, so I have to type every command by hand, with a wonky connection, so it's taking an extremely long time to debug this stuff)
If you are trying to find all the non null column values for a particular record you could try an unpivot provided all the columns you are unpivoting have the same data type:
SELECT *
FROM (select * from my_table where name like '%unique value%')
UNPIVOT [include nulls] (col_value FOR col_name IN (col1, col2, ..., coln))
with the above code null values will be excluded unless you include the optional include nulls statement, also you will need to explicitly list each column you want unpivoted.
If they don't all have the same data type, you can use a variation that doesn't necessarily prune away all the null values:
select *
from (select * from my_table where name like '%unique value%')
unpivot ((str_val, num_val, date_val)
for col_name in ((cola, col1, date1)
,(colb, col2, date2)
,(colc, col3, date1)));
You can have a fairly large set of column groups, though here I'm showing just three, one for each major data type, with the IN list you need to have a column listed for each column in your column group, though you can reuse columns as shown by the date_val column where I've used date1 twice. As an alternative to reusing an existing column, you could use a dummy column with a null value:
select *
from (select t1.*, null dummy from my_table t1 where name like '%unique value%')
unpivot ((str_val, num_val, date_val)
for col_name in ((dummy, col1, date1)
,(colb, dummy, date2)
,(colc, col3, dummy)));
Have tried this?
SELECT * FROM my_table WHERE NAME LIKE '%unique name%' AND value IS NOT NULL;
Oracle / PLSQL: IS NOT NULL Condition
For row number:
SELECT field1, field2, ROW_NUMBER() OVER (PARTITION BY unique_field) R WHERE R=1;
Usually in Linux consoles you can use arrow up&down to repeat the last sentence.
I have 2 tables that are the same structure. One is a temp one and the other is a prod one. The entire data set gets loaded each time and sometimes this dataset will have deleted records from the prior datasets. I load the dataset into temp table first and if any records were deleted I want to deleted them from the prod table also.
So how can I find the records that exist in prod but not in temp? I tried outer join but it doesn't seem to be working. It's returning all the records from the table in the left or right depending on doing left or right outer join.
I then also want to delete those records in the prod table.
One way would be to use the MINUS operator
SELECT * FROM table1
MINUS
SELECT * FROM table2
will show all the rows in table1 that do not have an exact match in table2 (you can obviously specify a smaller column list if you are only interested in determining whether a particular key exists in both tables).
Another would be to use a NOT EXISTS
SELECT *
FROM table1 t1
WHERE NOT EXISTS( SELECT 1
FROM table2 t2
WHERE t1.some_key = t2.some_key )
How about something like:
SELECT * FROM ProdTable WHERE ID NOT IN
(select ID from TempTable);
It'd work the same as a DELETE statement as well:
DELETE FROM ProdTable WHERE ID NOT IN
(select ID from TempTable);
MINUS can work here
The following statement combines results with the MINUS operator, which returns only rows returned by the first query but not by the second:
SELECT * FROM prod
MINUS
SELECT * FROM temp;
Minus will only work if the table structure is same
I have this DML statement..
delete from (select key,value,computed, row_number() OVER (Partition By key, value order by seq asc) as a
from excelformats a )
where A > 1
and this throws
ORA-01732: data manipulation operation not legal on this view
This statement basically selects duplicate rows from excelFormats table those to be deleted
How can I revise so that
You could use:
DELETE FROM excelformats
WHERE rowid not in
(SELECT MIN(rowid)
FROM excelformats
GROUP BY key, value, computed);
This will delete duplicate rows in your excelformats table given the three key columns you stated.
Hope it helps...