diff --git a/neutrino-proxy-server/src/main/resources/sql/h2/init-structure.sql b/neutrino-proxy-server/src/main/resources/sql/h2/init-structure.sql
index a1721cf6..01dd93e8 100644
--- a/neutrino-proxy-server/src/main/resources/sql/h2/init-structure.sql
+++ b/neutrino-proxy-server/src/main/resources/sql/h2/init-structure.sql
@@ -135,7 +135,7 @@ CREATE TABLE IF NOT EXISTS `domain_port_mapping` (
     `domain_name_id` INTEGER NOT NULL,
     `port_mapping_id` INTEGER NOT NULL
 );
-CREATE UNIQUE INDEX IF NOT EXISTS I_unique_domain_port_mapping ON domain_port_mapping (`domain_name_id` ASC, `port_mapping_id` ASC, `subdomain` ASC);
+CREATE UNIQUE INDEX IF NOT EXISTS I_unique_domain_port_mapping ON domain_port_mapping (`domain_name_id` ASC, `subdomain` ASC);
 CREATE INDEX IF NOT EXISTS I_domain_port_mapping_domain_name_id ON domain_port_mapping (`domain_name_id` ASC);
 CREATE INDEX IF NOT EXISTS I_domain_port_mapping_port_mapping_id ON domain_port_mapping (`port_mapping_id` ASC);
 
diff --git a/neutrino-proxy-server/src/main/resources/sql/h2/update/UPDATE-20240808.SQL b/neutrino-proxy-server/src/main/resources/sql/h2/update/UPDATE-20240808.SQL
index b3c4ca7c..c81fad99 100644
--- a/neutrino-proxy-server/src/main/resources/sql/h2/update/UPDATE-20240808.SQL
+++ b/neutrino-proxy-server/src/main/resources/sql/h2/update/UPDATE-20240808.SQL
@@ -20,7 +20,7 @@ CREATE TABLE IF NOT EXISTS `domain_port_mapping` (
     `domain_name_id` INTEGER NOT NULL,
     `port_mapping_id` INTEGER NOT NULL
     );
-CREATE UNIQUE INDEX IF NOT EXISTS I_unique_domain_port_mapping ON domain_port_mapping (`domain_name_id` ASC, `port_mapping_id` ASC, `subdomain` ASC);
+CREATE UNIQUE INDEX IF NOT EXISTS I_unique_domain_port_mapping ON domain_port_mapping (`domain_name_id` ASC, `subdomain` ASC);
 CREATE INDEX IF NOT EXISTS I_domain_port_mapping_domain_name_id ON domain_port_mapping (`domain_name_id` ASC);
 CREATE INDEX IF NOT EXISTS I_domain_port_mapping_port_mapping_id ON domain_port_mapping (`port_mapping_id` ASC);