基于目标和源的Oracle合并

Question

I need to execute below in oracle but this is not compatible. Basically based on target and source. Can any one suggest any alternative using SQL only :

merge into x as target using y as Source on target.ID = Source.ID
when not matched by target then insert
when matched then update
when not matched by source and target.ID is not null then
update whatevercolumn = 'isdeleted'

Answer 1

The format for a typical merge statement is something along the lines of:

merge into target_table tgt
using source_dataset src
  on (<join conditions>)
when matched then
  update set tgt.col1 = src.col1,
             tgt.col2 = src.col2, 
             ...
  where <predicates, if required>
when not matched then
  insert (tgt.col1, tgt.col2, ...)
  values (src.col1, src.col2, ...);

You'll have to amend your logic into this format if you want the merge to work.

If you can't do this, please update your question with sample data from the target and source tables, and the outcome you're expecting, along with the logic behind the update you're trying to do.

---

If you need to update records in your target table that don't appear in your source data as well as records that do appear, then you'll need to write a subquery that does a full outer join between both tables and then use that as your source dataset.

Something like:

merge into target_table trg
using (select coalesce(srce.target_join_col, targ.source_join_col) join_col,
              coalesce(srce.other_col1, targ.other_col1) other_col1,
              coalesce(srce.other_col2, targ.other_col2) other_col2,
              ...
       from   target_table targ
              full outer join source_table srce on (targ.target_join_col = srce.source_join_col)) src
  on (trg.target_join_col)
when matched then
  update set trg.other_col1 = src.other_col1,
             trg.other_col2 = src.other_col2,
             ...
  where      trg.other_col1 != src.other_col1
  or         trg.other_col2 != src.other_col2
  ...
when not matched then
  insert (trg.target_join_col, trg.other_col1, trg.other_col2, ...)
  values (src.source_join_col, src.other_col1, src.other_col2, ...);

NB untested, since you didn't provide any test case or data for us to work with.