Thanks again @magnusbaeck.
Now lets say i'm having a
string type column called
name and before running the
sql_last_value is empty. I'm having values as
text1, text2, text3.. under the column
So if I'm going to upload the db records through
logstash to the index with some way of comparing strings in the SQL dialect, what if there're two records having the same string value for the
name column ? Will
sql_last_value compare two of them and assume it as a duplicate?
UPPER(column_name) mean in
UPPER(column_name) > UPPER(:sql_last_value)?
> : in the SQL dialect means to check if the value is greater than the existing
sql_last_value isn't it ? So how can it compare when it comes to a string?