PL/SQL tutorial 17: Make synchronized backup copy of a table using DML Trigger

[@shreeratan567]

bro code is perfect and i'm in love with your explaination.you are G.O.A.T!!

[@arungupta5528]

Nice video bro.. thanks for sharing your knowledge

[@CidaLunacorteecostura]

I liked this video and your explanation. Thank you!

[@khyatiist]

Awesome explanation Manish. Thanks for sharing. Please tell me what does 1=2 in the where clause mean? Sorry if that's basic but I have never used it.

[@Rebellionrider]

Thank you so much. I am glad that you liked my video. Your appreciation means a lot to me. Regarding 1=2, it is an always false condition, like 0>1 or True = False.

[@khyatiist]

@@Rebellionrider You deserve the appreciation Manish. Thanks for your prompt response. If it is a false condition then why is a where clause even needed?

[@achillles6838]

@@khyatiist it is used just to copy the structure of the table not the data. if you you want to copy the data and structure both then 1=1 is used.

[@amanmishra529]

hats off guruji :)

[@javaandroid6964]

Great explanation , why these channels have less views and likes

[@abdihakimmohamed6309]

Thank you Manish for the tutorial. Whenever I use the pseudo record :NEW or even :OLD I get an error I don't know why. I had to even copy the code from your blog but still throwing an error. I am using Oracle12c. There is a red line below the pseudo record. Help !!!!!!!!!!!

[@sahilehsan5728]

I had observe some cases. This trigger query is ok and will work absolutly with single column. But what about if I am having more than 50 columns in a table. How we can write update statement for that? Can you share me script as well for the above query.

[@aviksengupta4879]

can you please provide me a query? I have inserted one row values in a backup table, create TABLE_BK as select * from TABLE where DOC_ID = ABC; now I deleted DOC_ID = ABC from TABLE, now I need to insert all the values of row where DOC_ID = ABS from TABLW_BK to main TABLE.

[@ManojYadav-lc3by]

i need to create a backup copy of same table in different database and that should be updated when primary table is getting updated. is this possible with this trigger?

[@armanalirahul]

can you plz tell me why we use where expression? ( WHERE 1 = 2) in this query --> CREATE TABLE superheroes_backup AS SELECT * FROM superheroes WHERE 1=2;

[@rahulkumarprasad7803]

Hi Manish, I really respect your hard word and thank you once again that makes us to understand your videos. But I have a doubt . As you explain in this video that we can create synchronized backup copy of a table but what is the use of this back up table. I mean if we delete one record from main table , it will reflect in back up table too so could you please clear my doubt ??please any one ?

[@phuoccao4951]

same thoughts!

[@poojatr897]

Yes if we make any changes (insert/delete/update) in main table then obviously it reflects on backup table as we created backup table with condition 1=2. I hope you understood 😊

[@enriqueruiz3904]

Thanks for your time!!

[@bdub229]

Hi Great videos. I do have a question, Can you have multiple "SET column =:new.column WHERE column =:old.column;" in an ELSIF statement. I have created a movies table and if i wanted to update a certain column can this be done with "SET column =:new.column WHERE column =:old.column;" statement or is this something more advanced in some of your later tutorials? Thanks Bdub

[@pranaytanniru7764]

UPDATE table-name SET column-name = value, column-name = value, ... WHERE condition You can use this to update multiple columns

[@Faizyxyz]

Hi Manish Sir, I just want to know in this query INSERT INTO superheroes_backup (SH_NAME) VALUES (:NEW.SH_NAME); you have given superheroes_backup table name then after (SH_NAME) why so i am confused here why have you given this (SH_NAME)

[@pranaytanniru7764]

here it's optional, you can specify the column names while inserting in case if you are not inserting the data in the order of table columns or you want to insert data for only few columns.

[@gulzarsiddique8908]

can we use multiple columns in this program for backup ???

[@thulasireddy4514]

What is the difference between before and after

[@davidmakinde4291]

wonderful explanation. But i ran the same code and it compiles. But when i update or insert into the table, it tells me trigger compilation or authorisation error. Don't know why?

[@Rebellionrider]

Make sure the user through which you executing the trigger have all the necessary privileges for running it.

[@vikram4755]

Thanks that nice, but just a question, as you are executing this query in a one session hence you would be able to see insert, update and delete result. But if a user from different session views backup table, that would have nothing, as there is no commit!

[@Bhuvana9828]

We have to run commit command.

[@shikharchaudhary6984]

in oracle isql plus this is coming for same code , Warning: Trigger created with compilation errors . What to do ?

[@harshjain1207]

What does 1=2 means?? is 1 means table 1 and 2 means table 2???

[@SergeantTrigger]

it's a common statement/condition if u intend to duplicate a table but not copying it's content. 1=2 is false

[@Faizyxyz]

where 1=2 mean just creating the table with the same structure with out copying the data.

[@ahosanhabib9399]

faiza and sabillena, thank you :)

[@anushat2597]

How to get a copy of table along with constraints and indexes

[@CyberAZT]

Thanks

[@rameshas7184]

How to achieve this in oracle form plsql trigger

[@krishnasingh-ob6ob]

ORA-04079: invalid trigger specification give error all time

[@parag4982]

What us the purpose of 1=2?

[@sameer26121980]

Thanks for the explanation. What is the difference between BEFORE and AFTER? I tried creating a trigger with BEFORE. I made changes to the superheroes table.. alter table superheroes modify (sh_name integer); insert into superheroes (sh_name) values ('batman'); The main insert failed (as expected), but I did not see the record inserted into superheroes_bkp table. If the insert into superheroes_bkp table happens BEFORE the main table, then why the record is not visible in superheroes_bkp table? Or may be my understanding is wrong about BEFORE/AFTER. Is there a way to capture the insert even if the main insert fails?

[@rajanbansal1355]

want to know that we are writing keyword inserting deleting updating whether it is ok writing ing with insert delete update how system know that inserting means insert

[@codingwithtoaster8690]

They are predefined predicates in the oracle database. He talked about it in previous videos.

[@rahulkumarprasad7803]

Inserting is a keyword in Oracle.

[@zhengkeongng2892]

What does "where 1=2" means?

[@Rebellionrider]

It means "Always Not Equal". 1 will never be equal to 2. If you want you can also use 0=1 or 2 =9 whatever you feel comfortable with.

[@rahulkumarprasad7803]

Hey Manish .. I know you have a comment notification regarding this video .Please reply me the same.

[@Prasadd11]

what if i do delete from superheroes; update superheroes set sh_name='Ironman'; this trigger will not make a copy of the original table to backup table

[@marketingpaathshala3126]

what does this DESC means ?

[@codingwithtoaster8690]

describe

[@tarunsmdtp]

can we backup the data from one DB to another DB as well?