taler-merchant=# SELECT format(
  'DELETE FROM %I.merchant_kyc;',
  schema_name
)
FROM information_schema.schemata
WHERE schema_name LIKE 'merchant_instance_%';

 DELETE FROM merchant_instance_23.merchant_kyc;
 DELETE FROM merchant_instance_22.merchant_kyc;
 DELETE FROM merchant_instance_21.merchant_kyc;
 DELETE FROM merchant_instance_19.merchant_kyc;
 DELETE FROM merchant_instance_25.merchant_kyc;
 DELETE FROM merchant_instance_17.merchant_kyc;
 DELETE FROM merchant_instance_20.merchant_kyc;
 DELETE FROM merchant_instance_16.merchant_kyc;
 DELETE FROM merchant_instance_15.merchant_kyc;
 DELETE FROM merchant_instance_14.merchant_kyc;
 DELETE FROM merchant_instance_24.merchant_kyc;
 DELETE FROM merchant_instance_12.merchant_kyc;
 DELETE FROM merchant_instance_11.merchant_kyc;
 DELETE FROM merchant_instance_10.merchant_kyc;
 DELETE FROM merchant_instance_9.merchant_kyc;
 DELETE FROM merchant_instance_8.merchant_kyc;
 DELETE FROM merchant_instance_7.merchant_kyc;
 DELETE FROM merchant_instance_6.merchant_kyc;
 DELETE FROM merchant_instance_18.merchant_kyc;
 DELETE FROM merchant_instance_5.merchant_kyc;
 DELETE FROM merchant_instance_4.merchant_kyc;
 DELETE FROM merchant_instance_3.merchant_kyc;
 DELETE FROM merchant_instance_2.merchant_kyc;
 DELETE FROM merchant_instance_1.merchant_kyc;
(27 rows)

(END)

DO $$
DECLARE s text;
BEGIN
  FOR s IN
    SELECT schema_name
    FROM information_schema.schemata
    WHERE schema_name LIKE 'merchant_instance_%'
      AND schema_name <> 'merchant_instances'
  LOOP
    RAISE NOTICE 'Deleting from: %.merchant_kyc', s;
    EXECUTE format('DELETE FROM %I.merchant_kyc;', s);
  END LOOP;
END $$;

taler-merchant=# DO $$
DECLARE s text;
BEGIN
  FOR s IN
    SELECT schema_name
    FROM information_schema.schemata
    WHERE schema_name LIKE 'merchant_instance_%'
      AND schema_name <> 'merchant_instances'
  LOOP
    RAISE NOTICE 'Would delete from: %.merchant_kyc', s;
  END LOOP;
END $$;
NOTICE:  Would delete from: merchant_instance_27.merchant_kyc
NOTICE:  Would delete from: merchant_instance_26.merchant_kyc
NOTICE:  Would delete from: merchant_instance_23.merchant_kyc
NOTICE:  Would delete from: merchant_instance_22.merchant_kyc
NOTICE:  Would delete from: merchant_instance_21.merchant_kyc
NOTICE:  Would delete from: merchant_instance_19.merchant_kyc
NOTICE:  Would delete from: merchant_instance_25.merchant_kyc
NOTICE:  Would delete from: merchant_instance_17.merchant_kyc
NOTICE:  Would delete from: merchant_instance_20.merchant_kyc
NOTICE:  Would delete from: merchant_instance_16.merchant_kyc
NOTICE:  Would delete from: merchant_instance_15.merchant_kyc
NOTICE:  Would delete from: merchant_instance_14.merchant_kyc
NOTICE:  Would delete from: merchant_instance_24.merchant_kyc
NOTICE:  Would delete from: merchant_instance_12.merchant_kyc
NOTICE:  Would delete from: merchant_instance_11.merchant_kyc
NOTICE:  Would delete from: merchant_instance_10.merchant_kyc
NOTICE:  Would delete from: merchant_instance_9.merchant_kyc
NOTICE:  Would delete from: merchant_instance_8.merchant_kyc
NOTICE:  Would delete from: merchant_instance_7.merchant_kyc
NOTICE:  Would delete from: merchant_instance_6.merchant_kyc
NOTICE:  Would delete from: merchant_instance_18.merchant_kyc
NOTICE:  Would delete from: merchant_instance_5.merchant_kyc
NOTICE:  Would delete from: merchant_instance_4.merchant_kyc
NOTICE:  Would delete from: merchant_instance_3.merchant_kyc
NOTICE:  Would delete from: merchant_instance_2.merchant_kyc
NOTICE:  Would delete from: merchant_instance_1.merchant_kyc
DO
taler-merchant=#