diff --git a/backend/alembic/versions/018_modify_chat.py b/backend/alembic/versions/018_modify_chat.py
new file mode 100644
index 00000000..07a3e8ff
--- /dev/null
+++ b/backend/alembic/versions/018_modify_chat.py
@@ -0,0 +1,83 @@
+"""018_modify_chat
+
+Revision ID: 863105882eba
+Revises: a0ba8268868d
+Create Date: 2025-06-30 16:44:17.123791
+
+"""
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel.sql.sqltypes
+from sqlalchemy.dialects import postgresql
+
+# revision identifiers, used by Alembic.
+revision = '863105882eba'
+down_revision = 'a0ba8268868d'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.alter_column('chat', 'id',
+               existing_type=sa.INTEGER(),
+               type_=sa.BigInteger(),
+               existing_nullable=False,
+               autoincrement=True,
+               existing_server_default=sa.Identity(always=True, start=1, increment=1, minvalue=1, maxvalue=2147483647, cycle=False, cache=1))
+    op.alter_column('chat', 'datasource',
+               existing_type=sa.INTEGER(),
+               type_=sa.BigInteger(),
+               existing_nullable=True)
+    op.alter_column('chat_record', 'id',
+               existing_type=sa.INTEGER(),
+               type_=sa.BigInteger(),
+               existing_nullable=False,
+               autoincrement=True,
+               existing_server_default=sa.Identity(always=True, start=1, increment=1, minvalue=1, maxvalue=2147483647, cycle=False, cache=1))
+    op.alter_column('chat_record', 'chat_id',
+               existing_type=sa.INTEGER(),
+               type_=sa.BigInteger(),
+               existing_nullable=False)
+    op.alter_column('chat_record', 'ai_modal_id',
+               existing_type=sa.INTEGER(),
+               type_=sa.BigInteger(),
+               existing_nullable=True)
+    op.alter_column('chat_record', 'datasource',
+               existing_type=sa.INTEGER(),
+               type_=sa.BigInteger(),
+               existing_nullable=True)
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.alter_column('chat_record', 'datasource',
+               existing_type=sa.BigInteger(),
+               type_=sa.INTEGER(),
+               existing_nullable=True)
+    op.alter_column('chat_record', 'ai_modal_id',
+               existing_type=sa.BigInteger(),
+               type_=sa.INTEGER(),
+               existing_nullable=True)
+    op.alter_column('chat_record', 'chat_id',
+               existing_type=sa.BigInteger(),
+               type_=sa.INTEGER(),
+               existing_nullable=False)
+    op.alter_column('chat_record', 'id',
+               existing_type=sa.BigInteger(),
+               type_=sa.INTEGER(),
+               existing_nullable=False,
+               autoincrement=True,
+               existing_server_default=sa.Identity(always=True, start=1, increment=1, minvalue=1, maxvalue=2147483647, cycle=False, cache=1))
+    op.alter_column('chat', 'datasource',
+               existing_type=sa.BigInteger(),
+               type_=sa.INTEGER(),
+               existing_nullable=True)
+    op.alter_column('chat', 'id',
+               existing_type=sa.BigInteger(),
+               type_=sa.INTEGER(),
+               existing_nullable=False,
+               autoincrement=True,
+               existing_server_default=sa.Identity(always=True, start=1, increment=1, minvalue=1, maxvalue=2147483647, cycle=False, cache=1))
+    # ### end Alembic commands ###
diff --git a/backend/apps/chat/curd/chat.py b/backend/apps/chat/curd/chat.py
index 80b93b22..bf204645 100644
--- a/backend/apps/chat/curd/chat.py
+++ b/backend/apps/chat/curd/chat.py
@@ -61,7 +61,7 @@ def get_chat_with_records(session: SessionDep, chart_id: int, current_user: Curr
                   ChatRecord.question, ChatRecord.sql_answer, ChatRecord.sql, ChatRecord.data,
                   ChatRecord.chart_answer, ChatRecord.chart, ChatRecord.analysis, ChatRecord.predict,
                   ChatRecord.datasource_select_answer, ChatRecord.recommended_question_answer,
-                  ChatRecord.recommended_question,
+                  ChatRecord.recommended_question, ChatRecord.first_chat,
                   ChatRecord.predict_data, ChatRecord.finish, ChatRecord.error, ChatRecord.run_time)).filter(
         and_(Chat.create_by == current_user.id, ChatRecord.chat_id == chart_id)).order_by(ChatRecord.create_time).all()
 
@@ -111,6 +111,29 @@ def create_chat(session: SessionDep, current_user: CurrentUser, create_chat_obj:
         chat_info.datasource_exists = True
         chat_info.datasource_name = ds.name
 
+    if require_datasource and ds:
+        # generate first empty record
+        record = ChatRecord()
+        record.chat_id = chat.id
+        record.datasource = ds.id
+        record.engine_type = ds.type_name
+        record.first_chat = True
+        record.finish = True
+        record.create_time = datetime.datetime.now()
+        record.create_by = current_user.id
+
+        _record = ChatRecord(**record.model_dump())
+
+        session.add(record)
+        session.flush()
+        session.refresh(record)
+        _record.id = record.id
+        session.commit()
+
+        # todo suggest questions
+
+        chat_info.records.append(_record)
+
     return chat_info
 
 
@@ -131,6 +154,7 @@ def save_question(session: SessionDep, current_user: CurrentUser, question: Chat
     record.create_by = current_user.id
     record.datasource = chat.datasource
     record.engine_type = chat.engine_type
+    record.ai_modal_id = question.ai_modal_id
 
     result = ChatRecord(**record.model_dump())
 
diff --git a/backend/apps/chat/models/chat_model.py b/backend/apps/chat/models/chat_model.py
index f5305b63..37325769 100644
--- a/backend/apps/chat/models/chat_model.py
+++ b/backend/apps/chat/models/chat_model.py
@@ -15,25 +15,25 @@ from apps.template.select_datasource.generator import get_datasource_template
 
 class Chat(SQLModel, table=True):
     __tablename__ = "chat"
-    id: Optional[int] = Field(sa_column=Column(Integer, Identity(always=True), primary_key=True))
+    id: Optional[int] = Field(sa_column=Column(BigInteger, Identity(always=True), primary_key=True))
     create_time: datetime = Field(sa_column=Column(DateTime(timezone=True), nullable=True))
     create_by: int = Field(sa_column=Column(BigInteger, nullable=True))
     brief: str = Field(max_length=64, nullable=True)
     chat_type: str = Field(max_length=20, default="chat")  # chat, datasource
-    datasource: int = Field(sa_column=Column(Integer, nullable=True))
+    datasource: int = Field(sa_column=Column(BigInteger, nullable=True))
     engine_type: str = Field(max_length=64)
 
 
 class ChatRecord(SQLModel, table=True):
     __tablename__ = "chat_record"
-    id: Optional[int] = Field(sa_column=Column(Integer, Identity(always=True), primary_key=True))
-    chat_id: int = Field(sa_column=Column(Integer, nullable=False))
-    ai_modal_id: Optional[int] = Field(sa_column=Column(Integer))
+    id: Optional[int] = Field(sa_column=Column(BigInteger, Identity(always=True), primary_key=True))
+    chat_id: int = Field(sa_column=Column(BigInteger, nullable=False))
+    ai_modal_id: Optional[int] = Field(sa_column=Column(BigInteger))
     first_chat: bool = Field(sa_column=Column(Boolean, nullable=True, default=False))
     create_time: datetime = Field(sa_column=Column(DateTime(timezone=True), nullable=True))
     finish_time: datetime = Field(sa_column=Column(DateTime(timezone=True), nullable=True))
     create_by: int = Field(sa_column=Column(BigInteger, nullable=True))
-    datasource: int = Field(sa_column=Column(Integer, nullable=True))
+    datasource: int = Field(sa_column=Column(BigInteger, nullable=True))
     engine_type: str = Field(max_length=64)
     question: str = Field(sa_column=Column(Text, nullable=True))
     sql_answer: str = Field(sa_column=Column(Text, nullable=True))
@@ -90,6 +90,7 @@ class ChatInfo(BaseModel):
 
 
 class AiModelQuestion(BaseModel):
+    ai_modal_id: int = None
     engine: str = ""
     db_schema: str = ""
     sql: str = ""
diff --git a/backend/apps/chat/task/llm.py b/backend/apps/chat/task/llm.py
index 5935f9f9..8cc9d80c 100644
--- a/backend/apps/chat/task/llm.py
+++ b/backend/apps/chat/task/llm.py
@@ -39,6 +39,7 @@ class LLMService:
                  ds: CoreDatasource = None):
         self.ds = ds
         self.chat_question = chat_question
+        self.chat_question.ai_modal_id = aimodel.id
         self.config = get_llm_config(aimodel)
 
         # Create LLM instance through factory
diff --git a/frontend/src/api/chat.ts b/frontend/src/api/chat.ts
index 58a03ef4..3b9c7e31 100644
--- a/frontend/src/api/chat.ts
+++ b/frontend/src/api/chat.ts
@@ -22,7 +22,7 @@ export interface ChatMessage {
   content?: string | number
   record?: ChatRecord
   isTyping?: boolean
-  isWelcome?: boolean
+  first_chat?: boolean
 }
 
 export class ChatRecord {
@@ -42,6 +42,7 @@ export class ChatRecord {
   finish?: boolean = false
   error?: string
   run_time: number = 0
+  first_chat: boolean = false
 
   constructor()
   constructor(
@@ -60,7 +61,8 @@ export class ChatRecord {
     predict_data: string | undefined,
     finish: boolean,
     error: string | undefined,
-    run_time: number
+    run_time: number,
+    first_chat: boolean
   )
   constructor(
     id?: number,
@@ -78,7 +80,8 @@ export class ChatRecord {
     predict_data?: string,
     finish?: boolean,
     error?: string,
-    run_time?: number
+    run_time?: number,
+    first_chat?: boolean
   ) {
     this.id = id
     this.chat_id = chat_id
@@ -93,9 +96,10 @@ export class ChatRecord {
     this.analysis = analysis
     this.predict = predict
     this.predict_data = predict_data
-    this.finish = finish
+    this.finish = !!finish
     this.error = error
     this.run_time = run_time ?? 0
+    this.first_chat = !!first_chat
   }
 }
 
@@ -214,7 +218,8 @@ function toChatRecord(data?: any): ChatRecord | undefined {
     data.predict_data,
     data.finish,
     data.error,
-    data.run_time
+    data.run_time,
+    data.first_chat
   )
 }
 
diff --git a/frontend/src/utils/request.ts b/frontend/src/utils/request.ts
index cf9e54b4..957cdc15 100644
--- a/frontend/src/utils/request.ts
+++ b/frontend/src/utils/request.ts
@@ -217,6 +217,10 @@ class HttpService {
     if (token) {
       heads['X-SQLBOT-TOKEN'] = `Bearer ${token}`
     }
+    // @ts-ignore
+    const request_key = LicenseGenerator.generate()
+    heads['X-SQLBOT-KEY'] = request_key
+
     const real_url = import.meta.env.VITE_API_BASE_URL
     return fetch(real_url + url, {
       method: 'POST',
diff --git a/frontend/src/views/chat/ChatRecordFirst.vue b/frontend/src/views/chat/ChatRecordFirst.vue
new file mode 100644
index 00000000..8293a36d
--- /dev/null
+++ b/frontend/src/views/chat/ChatRecordFirst.vue
@@ -0,0 +1,45 @@
+<script setup lang="ts">
+import ChatBlock from './ChatBlock.vue'
+import { ChatInfo, type ChatMessage } from '@/api/chat.ts'
+import { computed } from 'vue'
+import { useI18n } from 'vue-i18n'
+
+const { t } = useI18n()
+const props = defineProps<{
+  msg: ChatMessage
+  currentChat: ChatInfo
+}>()
+
+const show = computed(() => {
+  return props.msg.first_chat
+})
+</script>
+
+<template>
+  <ChatBlock v-if="show">
+    <div class="welcome-content">
+      <div class="ds-select-row">
+        <div>{{ t('qa.selected_datasource') }}:</div>
+      </div>
+      <div>
+        {{ currentChat.datasource_name }}
+      </div>
+    </div>
+  </ChatBlock>
+</template>
+
+<style scoped lang="less">
+.welcome-content {
+  padding: 12px;
+  display: flex;
+}
+
+.sub {
+  color: grey;
+  font-size: 0.8em;
+}
+
+.ds-select-row {
+  margin-right: 8px;
+}
+</style>
diff --git a/frontend/src/views/chat/ChatRow.vue b/frontend/src/views/chat/ChatRow.vue
index 3c28e55f..cdfa8636 100644
--- a/frontend/src/views/chat/ChatRow.vue
+++ b/frontend/src/views/chat/ChatRow.vue
@@ -1,31 +1,16 @@
 <script setup lang="ts">
 import ChatBlock from './ChatBlock.vue'
-import WelcomeBlock from './WelcomeBlock.vue'
+import ChatRecordFirst from './ChatRecordFirst.vue'
 import { ChatInfo, type ChatMessage } from '@/api/chat.ts'
-import { computed } from 'vue'
 import { UserFilled } from '@element-plus/icons-vue'
 
-const props = withDefaults(
+withDefaults(
   defineProps<{
     msg: ChatMessage
     currentChat: ChatInfo
-    datasource?: number
   }>(),
-  {
-    datasource: undefined,
-  }
+  {}
 )
-
-const emits = defineEmits(['update:datasource'])
-
-const _datasource = computed({
-  get() {
-    return props.datasource
-  },
-  set(v) {
-    emits('update:datasource', v)
-  },
-})
 </script>
 
 <template>
@@ -36,13 +21,13 @@ const _datasource = computed({
         <UserFilled />
       </el-icon>
     </el-avatar>
-    <ChatBlock v-if="!msg.isWelcome" :msg="msg" :class="{ 'row-full': msg.role === 'assistant' }">
+    <ChatBlock v-if="!msg.first_chat" :msg="msg" :class="{ 'row-full': msg.role === 'assistant' }">
       <slot></slot>
       <template #footer>
         <slot name="footer"></slot>
       </template>
     </ChatBlock>
-    <WelcomeBlock v-else v-model="_datasource" :current-chat="currentChat" class="row-full" />
+    <ChatRecordFirst v-else :current-chat="currentChat" :msg="msg" />
   </div>
 </template>
 
diff --git a/frontend/src/views/chat/WelcomeBlock.vue b/frontend/src/views/chat/WelcomeBlock.vue
deleted file mode 100644
index c544b91b..00000000
--- a/frontend/src/views/chat/WelcomeBlock.vue
+++ /dev/null
@@ -1,182 +0,0 @@
-<script setup lang="ts">
-import ChatBlock from './ChatBlock.vue'
-import { ChatInfo } from '@/api/chat.ts'
-import { computed, onMounted, ref } from 'vue'
-import { datasourceApi } from '@/api/datasource.ts'
-import DatasourceItemCard from '../ds/DatasourceItemCard.vue'
-import { useI18n } from 'vue-i18n'
-
-const { t } = useI18n()
-const props = withDefaults(
-  defineProps<{
-    modelValue?: number
-    currentChat: ChatInfo
-  }>(),
-  {
-    modelValue: undefined,
-  }
-)
-
-const dsList = ref<Array<any>>([])
-
-const editable = computed(() => {
-  return props.currentChat?.id === undefined
-})
-
-const ds = computed(() => {
-  for (let i = 0; i < dsList.value.length; i++) {
-    const item = dsList.value[i]
-    if (props.modelValue === item.id) {
-      return item
-    }
-  }
-  if (props.currentChat && props.currentChat.datasource !== undefined) {
-    return {
-      id: props.currentChat.datasource,
-      name: props.currentChat.datasource_name ?? 'Datasource does not exist',
-      type: props.currentChat.engine_type,
-    }
-  }
-  return undefined
-})
-
-const emits = defineEmits(['update:modelValue'])
-
-function selectDs(ds: any) {
-  if (editable.value) {
-    emits('update:modelValue', ds.id)
-  }
-}
-
-function listDs() {
-  datasourceApi.list().then((res) => {
-    dsList.value = res
-  })
-}
-
-const dialogVisible = ref(false)
-
-const DatasourceListRef = ref()
-
-const innerDs = ref()
-
-function showDs() {
-  innerDs.value = props.modelValue
-  listDs()
-  dialogVisible.value = true
-}
-
-function selectDsInDialog(ds: any) {
-  innerDs.value = ds.id
-}
-
-function confirmSelectDs() {
-  if (innerDs.value) {
-    emits('update:modelValue', innerDs.value)
-    dialogVisible.value = false
-  }
-}
-
-onMounted(() => {
-  listDs()
-})
-</script>
-
-<template>
-  <ChatBlock>
-    <div class="welcome-content">
-      <div>{{ t('qa.greeting') }}</div>
-      <div class="sub">{{ t('qa.description') }}</div>
-      <template v-if="editable">
-        <template v-if="dsList.length > 0">
-          <div class="ds-select-row">
-            <div>{{ t('qa.select_datasource') }}</div>
-            <el-button link type="primary" @click="showDs">{{ t('qa.view_more') }}</el-button>
-          </div>
-          <div class="ds-row-container">
-            <template v-for="(item, _index) in dsList" :key="_index">
-              <DatasourceItemCard
-                v-if="_index < 3 || item?.id === modelValue"
-                :ds="item"
-                class="ds-card"
-                :class="[item?.id === modelValue ? 'ds-card-selected' : '']"
-                @click="selectDs(item)"
-              />
-            </template>
-          </div>
-        </template>
-        <div v-else>
-          {{ t('qa.empty_datasource') }}
-        </div>
-      </template>
-      <template v-else>
-        <div class="ds-select-row">
-          <div>{{ t('qa.selected_datasource') }}</div>
-        </div>
-        <div class="ds-row-container">
-          <DatasourceItemCard :ds="ds" />
-        </div>
-      </template>
-    </div>
-
-    <el-drawer
-      ref="DatasourceListRef"
-      v-model="dialogVisible"
-      title="Choose Datasource"
-      direction="btt"
-      size="100%"
-    >
-      <el-scrollbar>
-        <div class="ds-row-container">
-          <template v-for="(item, _index) in dsList" :key="_index">
-            <DatasourceItemCard
-              :ds="item"
-              class="ds-card"
-              :class="[item?.id === innerDs ? 'ds-card-selected' : '']"
-              @click="selectDsInDialog(item)"
-            />
-          </template>
-        </div>
-      </el-scrollbar>
-      <template #footer>
-        <div class="dialog-footer">
-          <el-button @click="dialogVisible = false">Cancel</el-button>
-          <el-button type="primary" @click="confirmSelectDs"> Confirm </el-button>
-        </div>
-      </template>
-    </el-drawer>
-  </ChatBlock>
-</template>
-
-<style scoped lang="less">
-.welcome-content {
-  padding: 12px;
-}
-
-.sub {
-  color: grey;
-  font-size: 0.8em;
-}
-
-.ds-select-row {
-  display: flex;
-  align-items: center;
-  flex-direction: row;
-  justify-content: space-between;
-}
-
-.ds-row-container {
-  display: grid;
-  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
-  gap: 24px;
-}
-
-.ds-card {
-  cursor: pointer;
-}
-
-.ds-card-selected {
-  box-shadow: 0 1px 3px var(--ed-color-primary-light-5);
-  border: 1px solid var(--ed-color-primary-light-5);
-}
-</style>
diff --git a/frontend/src/views/chat/index.vue b/frontend/src/views/chat/index.vue
index 71ba0070..12ce52cd 100644
--- a/frontend/src/views/chat/index.vue
+++ b/frontend/src/views/chat/index.vue
@@ -39,11 +39,7 @@
         </div>
         <el-scrollbar v-if="computedMessages.length > 0" ref="chatListRef">
           <template v-for="(message, _index) in computedMessages" :key="_index">
-            <ChatRow
-              v-model:datasource="currentChat.datasource"
-              :current-chat="currentChat"
-              :msg="message"
-            >
+            <ChatRow :current-chat="currentChat" :msg="message">
               <template v-if="message.role === 'assistant'">
                 <ChatAnswer v-slot="{ data }" :message="message">
                   <template v-if="message.record?.chart">
@@ -172,21 +168,13 @@ const isAnalysisTyping = ref<boolean>(false)
 const isPredictTyping = ref<boolean>(false)
 
 const computedMessages = computed<Array<ChatMessage>>(() => {
-  const firstMessage: ChatMessage = {
-    role: 'assistant',
-    create_time: currentChat.value?.create_time,
-    content: currentChat.value?.datasource,
-    isTyping: false,
-    isWelcome: true,
-  }
   const messages: Array<ChatMessage> = []
   if (currentChatId.value === undefined) {
     return messages
   }
-  messages.push(firstMessage)
   for (let i = 0; i < currentChat.value.records.length; i++) {
     const record = currentChat.value.records[i]
-    if (record.question !== undefined) {
+    if (record.question !== undefined && !record.first_chat) {
       messages.push({
         role: 'user',
         create_time: record.create_time,
@@ -198,9 +186,12 @@ const computedMessages = computed<Array<ChatMessage>>(() => {
       create_time: record.create_time,
       record: record,
       isTyping: i === currentChat.value.records.length - 1 && isTyping.value,
+      first_chat: record.first_chat,
     })
   }
 
+  console.log(messages)
+
   return messages
 })
 
@@ -283,7 +274,6 @@ onMounted(() => {
 
 const sendMessage = async () => {
   if (!inputMessage.value.trim()) return
-  if (computedMessages.value[0].content === undefined) return
 
   loading.value = true
   isTyping.value = true