The purpose of the application I'm trying to develop is to automatically create Can you provide me an example where it doesn't? What I try to show in this example is that it seems that unless the column/table is dropped it will have the same rowid. Using the following query to check the rowid:Īlter table mamv.teste modify (column1 number(5), column2 varchar2(50)) Īlter table mamv.teste drop column column2 But my question is if for a given column that isn't dropped, only changed, will the rowid in sys.col$ change? For example:Ĭreate table mamv.teste(column1 number, column2 varchar2(30)) I know the rowids can and will be reused. The purpose of the application I'm trying to develop is to automatically create the scripts we put on our version control software Please suggest me is it safe to use ROWID to update records in STG_INBOUND table or need to have a running sequence as a primary key and make use of that in the Where clause? SHRINK SPACE Command during this data processing (even no where in the database itself). we use ROWID to update the PROCESSED_FLAG = Y or PROCESSED_FLAG ='N', is this a right approch to follow? i need your inputs in this scenario.Īlso we are not performing any updates on the PARTITION_KEY results in ROW_MOVEMENT & not even issuing ALTER TABLE. once the file is completely processed without errors then partition is Dropped.ġ) we dont have any primary key in the STG_INBOUND table. The table STG_INBOUND is partitioned by the FILE_KEY Column for each new file loaded by Sql loader that has a reference to the FILE_KEY in STG_FILEMASTER table. if any error in the data then it will be marked to 'N' and start processing the next record. once completed the PROCESSED_FLAG in the table is marked to 'Y'. Once the data is loaded completely application will start processing the data. where Pipe Delimited data from flatfile is loaded into the table using SQL loader. Note, you need to combine with this some form of LOST UPDATE protection as well !!! You cannot just update by rowid and primary key - unless you locked the row when you read it out, else you will overwrite other peoples changes blindly. We can use the rowid to find the row (fast) and assuming it is still there update it. It is perfectly safe to use the rowid in ALL CASES however, assuming you combine it with the primary key as well: If you use alter table t move, the rowid could change (even without enable row movement) If you use alter table t shrink space compact, the rowid could change Meaning a row in a partitioned table - if you update the partition key and the update causes the row to move from one partition to another - the rowid will CHANGE. However, rows can be deleted+inserted by various commands "transparently", IF the DBA/table owner has set the "enable row movement" clause on the table. Gave me the same rows and the same rowids.ĭo ROWIDs ever change? If yes, how could I easily reproduce it?Ī rowid is assigned to a row upon insert and is imutable (never changing) unless the row is deleted and re-inserted (meaning it is another row, not the same row!) I got different rows, so I guess pages were split when I updated c to a wide value. ' asdfha sdfhaj sdhf asdhlf asldfh ajlskdfh jklasdh fjasdhf jlaksh dfjlashdfjashdfa sdjklfhalsdfhajlsdhflashdflasdhflasd' Select rowid r,i,c from a where rownum<100 Insert into a select some_numeric_column, 'a' from table_500K_rows I'm looking at a client application which retrieves several columns including ROWID, and later uses ROWID to identify rows it needs to update:Īs the table is being modified, can ROWID of a row change?Ĭreate table a(i number, c varchar2(250))
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