Updating using cursor oracle Scranton pennsylvania girl on xnxx com
You cannot use the update of a join in this case because the database currently wants you to JOIN to T on all of these columns - selecting where fld_name ='A' is insufficient.
However, we can use merge to do this in bulk: update (select t.value,s.value new_value 2 from t, s 3 where = s.key_to_t 4 and s.fld_name = 'A') 5 set value = new_value 6 / set value = new_value * ERROR at line 5: ORA-01779: cannot modify a column which maps to a non key-preserved table ops$tkyte%ORA10GR2 MERGE INTO T USING (SELECT * FROM S WHERE FLD = 'A') S ON (T. OLD_VALUE) WHEN MATCHED THEN UPDATE SET VALUE = OLD_VALUE; UPDATE allows me to join on VALUE but MERGE dont i get the error.
LAST UPDATE /* PARALLEL(TEMP_TABLE 12) */ TEMP_TABLE NOLOGGING SET NROW_ID = ROW_ID WHERE ROWID = ROWID_TAB(I) AND ROW_ID IS NULL; COMMIT; END LOOP; CLOSE REC_CUR; END; Against this above procedure one of our DBA make a comment as mentioned below : "This update is based on 'rowid' column that is a hidden pseudo column, and not a part of the table definition.
So it may be quicker to do the update in a single statement.
You are not required to make changes to the records in order to use this statement.
The record locks are released when the next commit or rollback statement is issued.
given this as the case what is the best way to perform this update update t set t.value = (select new_value from s where t.value = s.value and s.fld_name = 'A') where exists (select new_value from s where t.value = s.value and s.fld_name = 'A') but using exists is very expencive for me. I modified your example - you update value, but you joined on value, so the update would do nothing.
My mentor told me that when querying data I should always use a cursor FOR loop, even for a single row lookup. It’s great to learn from others, and it’s especially wonderful when the lesson you learn is simple and easy to remember.
From last few days I came across many situations where I need to update a table based on some analytical function output.
Since, my table don't have any primary key I am having limitation on update using SQL and hence I left with the only alternatives of using PL/SQL.
Using the cursor FOR loop construct is a declarative way of asking Oracle Database to fetch each of the rows specified by your cursor and then execute the loop body for that row.
You don’t have to explicitly open the cursor, code the fetch, check to see if the cursor is exhausted, or close the cursor. The problem with using a cursor FOR loop is that either it isn’t the appropriate construct for querying data (as is the case for a single-row fetch) or it isn’t the most efficient approach (BULK COLLECT offers a faster way of querying data).
ERROR at line 3: ORA-38104: Columns referenced in the ON Clause cannot be updated: "T"."VALUE" you wrote " ... May be that way we can understand MERGE in a better way. Attribute ID AND ( 6 CASE WHEN LOWER(s.value) = LOWER(p.value) THEN 1 ELSE 2 END = 2 OR 7 CASE WHEN LOWER(s.value) = LOWER(p.value) THEN 1 ELSE 2 END = 2 8 ) 9 ) 10 WHEN MATCHED THEN 11 UPDATE SET p.