Update scripts/sql/export_valid_responses.sql

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Steph Housden <167300771+stephhou@users.noreply.github.com>

Author: stephhou

scripts/sql/export_valid_responses.sql

@@ -1,6 +1,6 @@
 -- SQL script to export a csv file containing NHS numbers of submitted responses to a folder on an AVD.
 -- A valid response is defined as a response where the user has submitted the questionnaire.
--- Run script using psql command line tool or pgAdmin query tool on AVD.
+-- Run script using the psql command line tool on AVD; this file uses psql meta-commands (\set, \copy) and will not run in pgAdmin Query Tool.
 
 \set ON_ERROR_STOP on
 \copy (SELECT DISTINCT qu.nhs_number FROM questions_user qu JOIN questions_responseset qrs ON qrs.user_id = qu.id WHERE qrs.submitted_at IS NOT NULL) TO 'C:/Users/*YourUsername*/Documents/valid_responses.csv' WITH (FORMAT csv, HEADER true);