Updating columns in oracle why be friends before dating

This may seem like a simple question: Update Column a1 in Table A with all data in Column b1 in Table B. I have a table named A containing say 100000 records. HSCODELIST 5 WHERE not exists 6 (SELECT NULL FROM VIStemp. Brao what I suggest then is not to do it in a single sql statement -- just proving that "there are exceptions to every rule". Type ----------------------------------------- -------- ---------------------------- BIN VARCHAR2(10) ACT_SL VARCHAR2(3) ACT_CODE VARCHAR2(11) ACT_VAL NUMBER(14,2) ENTRY_DATE DATE SQL DESC VIS. Type ----------------------------------------- -------- ---------------------------- BIN VARCHAR2(10) ACT_SL VARCHAR2(3) ACT_CODE VARCHAR2(11) ACT_VAL NUMBER(14,2) ENTRY_DATE DATE SQL UPDATE (SELECT DBHSCODELIST. the database needs to know that each row in dbhscodelist will map to AT MOST one row in hscodelist - this mandates a primary or unqiue key constraint on the join columns this is discussed in the original answer above.

But I am trapped by the method that without using cursor to achieve it. I have another table B containg 10,000 records of incremented and edited records of A table. I am using the following codes to append data from B to A. Normally, I would try to use a single sql statment -- here, due to the "data being spread all over the place", and being distributed and all. We have a 2 CPU machine where at normal times, the topmost entry in top command shows only .2 or .3 percentage of CPU use. This is on a test database where nothing else is going on concurrently.

We are going to update column DESCRIPTION and PICTURE in table Categories_Test by using data in table Categories, based on data in the common column CATEGORY_ID. Update data in a column in table A based on a common column in table B. Update data in two columns in table A based on a common column in table B. Conditionally update data in table A based on a common column in table B. No portion may be reproduced without my written permission.

The update query below shows that the PICTURE column is updated by looking up the same ID value in CATEGORY_ID column in table Categories_Test and Categories. If you need to update multiple columns simultaneously, use comma to separate each column after the SET keyword. Here we only want to update PICTURE column in Categories_Test table where the data in Category_Name column is Seafood in table Categories. Software and hardware names mentioned on this site are registered trademarks of their respective companies.

It works, but it won't tell you if the value changed, only that the column is being updated (even if the update doesn't change the value).

Now, the user is saying that when they select from blobtable (using PL/SQL developer), blobcol contains "Value Error" for this row. Out of curiosity, I tried selecting the same record in SQL*Plus and I get the following value for blobcol: CREATE DIRECTORY MY_DIR AS '/directory/subdirectory'; DECLARE src_bfile BFILE := BFILENAME('MY_DIR', 'filename.txt'); dest_blob BLOB; BEGIN SELECT BLOBCOL into dest_blob FROM BLOBTABLE WHERE ROWID = 'ROWIDVALUE'; DBMS_LOB.

Notice that the WHERE clause identifies which row will be updated with Oracle UPDATE SQL.

Question: I want to update multiple rows in my table, and I need to understand how to update multiple columns.

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