diff --git a/model/ddl.sql b/model/ddl.sql
index 6ae5de0..9976b13 100644
--- a/model/ddl.sql
+++ b/model/ddl.sql
@@ -104,7 +104,7 @@ CREATE TABLE PUBLIC.TOPOLOGIC (
 );
 
 CREATE TABLE PUBLIC.BAY (
-    ID BIGSERIAL PRIMARY KEY,
+    BAY_UUID UUID PRIMARY KEY DEFAULT GEN_RANDOM_UUID(),
   	NAME VARCHAR(64) NOT NULL DEFAULT '',
   	TYPE VARCHAR(64) NOT NULL DEFAULT '',
     UNOM DOUBLE PRECISION NOT NULL DEFAULT -1,
@@ -125,6 +125,7 @@ CREATE TABLE PUBLIC.BAY (
     DEV_DYN_SENSE JSONB NOT NULL DEFAULT '[]', -- devices
     DEV_INSTRUCT JSONB NOT NULL DEFAULT '[]', -- devices
     DEV_ETC JSONB NOT NULL DEFAULT '[]', -- devices
+    COMPONENTS UUID[] NOT NULL DEFAULT '{}',
     OP INTEGER NOT NULL DEFAULT -1,
     TS TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP 
 );
@@ -134,13 +135,13 @@ CREATE TABLE PUBLIC.MEASUREMENT (
     TAG VARCHAR(64) NOT NULL DEFAULT '',
     NAME VARCHAR(64) NOT NULL DEFAULT '',
     TYPE SMALLINT NOT NULL DEFAULT -1,
-    DATA_SOURCE JSONB NOT NULL DEFAULT '{}', -- {"type":1,"main_pos":"","sub_pos":""}
     SIZE INTEGER NOT NULL DEFAULT -1,
-    BAY_ID BIGINT NOT NULL,
+    DATA_SOURCE JSONB NOT NULL DEFAULT '{}', -- {"type":1,"main_pos":"","sub_pos":""}
+    BAY_UUID UUID NOT NULL,
     COMPONENT_UUID UUID NOT NULL,
     OP INTEGER NOT NULL DEFAULT -1,
     TS TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
 
-    FOREIGN KEY (BAY_ID) REFERENCES PUBLIC.BAY (ID),
+    FOREIGN KEY (BAY_UUID) REFERENCES PUBLIC.BAY (BAY_UUID),
     FOREIGN KEY (COMPONENT_UUID) REFERENCES PUBLIC.COMPONENT (GLOBAL_UUID)
 );
diff --git a/model/ddl_4_bay.sql b/model/ddl_4_bay.sql
index ae85d81..a6b0c8e 100644
--- a/model/ddl_4_bay.sql
+++ b/model/ddl_4_bay.sql
@@ -3,10 +3,10 @@
 -- DROP TABLE IF EXISTS PUBLIC.BAY;
 
 CREATE TABLE PUBLIC.BAY (
-    ID SERIAL PRIMARY KEY,
+    BAY_UUID UUID PRIMARY KEY DEFAULT GEN_RANDOM_UUID(),
   	NAME VARCHAR(64) NOT NULL DEFAULT '',
   	TYPE VARCHAR(64) NOT NULL DEFAULT '',
-    NOMINAL_VOLTAGE DOUBLE PRECISION NOT NULL DEFAULT -1,
+    UNOM DOUBLE PRECISION NOT NULL DEFAULT -1,
     FLA DOUBLE PRECISION NOT NULL DEFAULT -1,
     CAPACITY DOUBLE PRECISION NOT NULL DEFAULT -1,
     DESCRIPTION VARCHAR(512) NOT NULL DEFAULT '',
diff --git a/model/ddl_5_measurement.sql b/model/ddl_5_measurement.sql
index 18a9b8f..f20522c 100644
--- a/model/ddl_5_measurement.sql
+++ b/model/ddl_5_measurement.sql
@@ -9,11 +9,11 @@ CREATE TABLE PUBLIC.MEASUREMENT (
     TYPE SMALLINT NOT NULL DEFAULT -1,
     DATA_SOURCE JSONB NOT NULL DEFAULT '{}', -- {"type":1,"main_pos":"","sub_pos":""}
     SIZE INTEGER NOT NULL DEFAULT -1,
-    BAY_ID INTEGER NOT NULL DEFAULT -1,
+    BAY_UUID UUID NOT NULL,
     COMPONENT_UUID UUID NOT NULL,
     OP INTEGER NOT NULL DEFAULT -1,
     TS TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
 
-    FOREIGN KEY (BAY_ID) REFERENCES PUBLIC.BAY (ID),
+    FOREIGN KEY (BAY_UUID) REFERENCES PUBLIC.BAY (BAY_UUID),
     FOREIGN KEY (COMPONENT_UUID) REFERENCES PUBLIC.COMPONENT (GLOBAL_UUID)
 );
\ No newline at end of file
diff --git a/model/dml.sql b/model/dml.sql
index eebfd94..af8838d 100644
--- a/model/dml.sql
+++ b/model/dml.sql
@@ -1,5 +1,26 @@
 
 
+-- grid initialization example
+INSERT INTO 
+	PUBLIC.GRID (NAME, DESCRIPTION, OP)
+VALUES
+	('电网','电网的描述',1);
+
+
+-- zone initialization example
+INSERT INTO 
+	PUBLIC.ZONE (GRID_ID, NAME, DESCRIPTION, OP)
+VALUES
+	(1 ,'区域','区域的描述',1);
+
+
+-- station initialization example
+INSERT INTO 
+	PUBLIC.STATION (ZONE_ID, NAME, DESCRIPTION, IS_LOCAL, OP)
+VALUES
+	(1 ,'厂站','厂站的描述',TRUE,1);
+
+
 -- supported standard component type
 INSERT INTO 
 	PUBLIC.COMPONENT_TYPE (TYPE, NAME, CONFIG)
@@ -17,4 +38,6 @@ VALUES
 	('potential_indicator','带电指示器','{}'),
 	('lightning_arrester','避雷器','{}'),
 	('cable_termination','电缆出线套筒','{}'),
-	('cable_end','电缆端','{}');
\ No newline at end of file
+	('cable_end','电缆端','{}'),
+	('2w_transformer','两绕组变压器','{}'),
+	('3w_transformer','三绕组变压器','{}');
\ No newline at end of file