diff --git a/base_model/ddl.sql b/base_model/ddl.sql
index 248e0ec..99c19ee 100644
--- a/base_model/ddl.sql
+++ b/base_model/ddl.sql
@@ -22,6 +22,8 @@ CREATE TABLE BASIC.MODEL_TYPE (
 	ID BIGSERIAL PRIMARY KEY,
 	MODEL_TYPE VARCHAR(64) NOT NULL DEFAULT '',
 	MODEL_NAME VARCHAR(64) NOT NULL DEFAULT '',
+	GRAPHIC_ELEMENT VARCHAR(64) NOT NULL DEFAULT '', -- 图元类型
+	ICON BYTEA NOT NULL, -- 默认图标
 	REMARK VARCHAR(128) NOT NULL DEFAULT '',
 	
 	UNIQUE (MODEL_TYPE)
diff --git a/model/ddl_0_component_type.sql b/model/ddl_0_component_type.sql
index 0192f5b..1909e88 100644
--- a/model/ddl_0_component_type.sql
+++ b/model/ddl_0_component_type.sql
@@ -5,5 +5,7 @@ DROP TABLE IF EXISTS PUBLIC.COMPONENT_TYPE;
 CREATE TABLE PUBLIC.COMPONENT_TYPE (
     ID SERIAL PRIMARY KEY,
     TYPE VARCHAR(64) NOT NULL DEFAULT '',
-    NAME VARCHAR(64) NOT NULL DEFAULT ''
+    NAME VARCHAR(64) NOT NULL DEFAULT '',
+
+    UNIQUE (TYPE)
 );
\ No newline at end of file
diff --git a/model/ddl_0_measurement.sql b/model/ddl_0_measurement.sql
deleted file mode 100644
index 5d027ce..0000000
--- a/model/ddl_0_measurement.sql
+++ /dev/null
@@ -1,10 +0,0 @@
--- measurement of bay
-
-DROP TABLE IF EXISTS PUBLIC.MEASUREMENT;
-
-CREATE TABLE PUBLIC.MEASUREMENT (
-    ID SERIAL PRIMARY KEY,
-    TAG VARCHAR(64) NOT NULL DEFAULT '',
-    NAME VARCHAR(64) NOT NULL DEFAULT '',
-    BAY_ID INTEGER NOT NULL DEFAULT -1
-);
\ No newline at end of file
diff --git a/model/ddl_0_bay.sql b/model/ddl_4_bay.sql
similarity index 66%
rename from model/ddl_0_bay.sql
rename to model/ddl_4_bay.sql
index d318750..5fb3411 100644
--- a/model/ddl_0_bay.sql
+++ b/model/ddl_4_bay.sql
@@ -6,6 +6,6 @@ CREATE TABLE PUBLIC.BAY (
     ID SERIAL PRIMARY KEY,
   	NAME VARCHAR(64) NOT NULL DEFAULT '',
   	TYPE VARCHAR(64) NOT NULL DEFAULT '',
-  	FROM_NODE JSONB NOT NULL DEFAULT '{}',
-  	TO_NODE JSONB NOT NULL DEFAULT '{}'
+  	FROM_NODE JSONB NOT NULL DEFAULT '[]', -- uuids
+  	TO_NODE JSONB NOT NULL DEFAULT '[]' -- uuids
 );
\ No newline at end of file
diff --git a/model/ddl_5_measurement.sql b/model/ddl_5_measurement.sql
new file mode 100644
index 0000000..9536e1d
--- /dev/null
+++ b/model/ddl_5_measurement.sql
@@ -0,0 +1,14 @@
+-- measurement of component in bay
+
+DROP TABLE IF EXISTS PUBLIC.MEASUREMENT;
+
+CREATE TABLE PUBLIC.MEASUREMENT (
+    ID SERIAL PRIMARY KEY,
+    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':,'main_pos':'','sub_pos':''}
+    SIZE INTEGER NOT NULL DEFAULT -1,
+    BAY_ID INTEGER NOT NULL DEFAULT -1,
+    COMPONENT_ID INTEGER NOT NULL DEFAULT -1
+);
\ No newline at end of file