Updating one table from another sql server Phon hot chat sample
This is one of the most interesting questions I keep on getting on this email and I find that not everyone knows about it. Our requirement is that we have Table2 which has two rows where Col1 is 21 and 31. Can you please let me know what are the cases multipart identifier error message will be shown.
In recent times I have seen a developer writing a cursor to update a table. We want to update the value from Table2 to Table1 for the rows where Col1 is 21 and 31. I resolved this by providing the alias name after update query:: UPDATE Table1 SET Col2 = t2.
How can I read data from table #2 and update address and phone2 in table #1 with values from table #2 address and phone columns when gender and birthdate is the same in each row?
2) in this way, if I want join 2table and some columns in table #2 does not exist in table #1 I got any error?
for example if I have color column in table #2 and its not exist on table #1, join process got error or just join columns exist in 2tables?
works fine when I try to update all the records in tbl A, however, in this case I only have missing data which I have identified and populated in tbl B.
When I try to update only the missing data the non-matched data is also updated but to NULL. The reason some of your rows are getting NULLs updated is due to the subquery.
When the subquery fails to find a matching row in tbl B, the subquery returns NULL.