CODEWITHSUNDEEP
androidsqlitesql-update
kolyaseg
kolyaseg

Reputation: 543

Android SQLite: How to update one column of all records with different values

I found on Stack similar questions like this How to update an entire column in sqlite? But they don't explain me my how to solve my task.

Say, I have a db with 5 columns and 5 records in it. What i need is to update the last column "date" with the values of unix time that differs by 1 sec. So i need to put values 1406820974139, 1406820974140, 1406820974141, 1406820974142, 1406820974143, 1406820974144.

How to do it using ContentValues? As i got i have to loop five times to create new ContentValues object and update one record at a time (maybe using db.startTransaction() syntax).

My question is is there a way to put all values at a time into one ContentValues object and write in them into DB? Or maybe the better way is to use rawQuery using native SQL syntax as explained in How to update an entire column in sqlite?

Upvotes: 2

Views: 2787

Answers (2)

CL.
CL.

Reputation: 180060

In theory, it would be possible to put all the values into a single SQL statement:

UPDATE MyTable
SET date = CASE _id
           WHEN   5 THEN 1406820974139
           WHEN  17 THEN 1406820974140
           WHEN  23 THEN 1406820974141
           WHEN  69 THEN 1406820974142
           WHEN 666 THEN 1406820974143
           END;

However, just creating one ContentValues object for each row is easier than constructing this command.

Upvotes: 2

call me carrot
call me carrot

Reputation: 192

so that we know which date should go to which row? what is the cririteria to differentiate the rows?
a relational db table is different from say an excel table. there is no implicit row order (if you always see the rows in the same order,you can consider it a kind of coincidence,you can not rely on this like you do in excel), in a db table you need to have a column(or a group of them) with unique values which you use in your queries to identify each of your records. so you need to be more clear in your question. what date should go to which record (identified by what?). there is no implicit row number, if you want it, add an autoincrement PK column. then you could for instance use something along the lines of

  UPDATE table SET column5= 1406820974140+PKcolumn

where 1406820974140 is the start date you have to choose, depending on what you are up to

Upvotes: 0

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