How to put SQL query in Spring boot application in if function? - sql

Question

In my spring boot application in REQUEST i post streamName and in response I get key. I'm putting this into a database and I want to avoid repeating stream names. My plan is to add such query to the insertStream method and when it returns null value, i.e. there is no such name in the database, then INSERT will be performed. Unfortunately I do not know how to implement this in the code.
This is my method:
#Override
public int insertStream(String key, String streamName) {
String sql = "" +
"INSERT INTO stream (" +
" stream_name, " + " license_key )" + "VALUES (?,?)";
return jdbcTemplate.update(
sql,
streamName,
key
);
}
and this is mention example query:
SELECT count(*) FROM public.stream WHERE stream_name='live2';
but instead of live2 it will be streamName parameter

Answer 1

you can use upsert in postgrsql
add a unique constraint to the stream_name column
CREATE UNIQUE INDEX unq_stream_name on stream(stream_name);
ALTER TABLE stream
ADD CONSTRAINT unq_stream_name_const
UNIQUE USING INDEX unq_stream_name;
then do upsert:
insert into stream (stream_name, license_key)
values (?,?) on conflict do nothing;
if the stream_name already exists , nothing will be inserted.