diff --git a/src/connector/src/source/base.rs b/src/connector/src/source/base.rs
index d2b5aa1e88b4..59e3585431a6 100644
--- a/src/connector/src/source/base.rs
+++ b/src/connector/src/source/base.rs
@@ -243,6 +243,7 @@ pub enum SourceFormat {
     Plain,
 }
 
+/// Refer to [`crate::parser::EncodingProperties`]
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
 pub enum SourceEncode {
     #[default]
diff --git a/src/frontend/src/catalog/catalog_service.rs b/src/frontend/src/catalog/catalog_service.rs
index 5f42d1e73e5b..061aeb737aa3 100644
--- a/src/frontend/src/catalog/catalog_service.rs
+++ b/src/frontend/src/catalog/catalog_service.rs
@@ -95,8 +95,6 @@ pub trait CatalogWriter: Send + Sync {
         job_type: TableJobType,
     ) -> Result<()>;
 
-    async fn alter_source_column(&self, source: PbSource) -> Result<()>;
-
     async fn create_index(
         &self,
         index: PbIndex,
@@ -104,12 +102,10 @@ pub trait CatalogWriter: Send + Sync {
         graph: StreamFragmentGraph,
     ) -> Result<()>;
 
-    async fn create_source(&self, source: PbSource) -> Result<()>;
-
-    async fn create_source_with_graph(
+    async fn create_source(
         &self,
         source: PbSource,
-        graph: StreamFragmentGraph,
+        graph: Option<StreamFragmentGraph>,
     ) -> Result<()>;
 
     async fn create_sink(
@@ -199,7 +195,8 @@ pub trait CatalogWriter: Send + Sync {
 
     async fn alter_owner(&self, object: Object, owner_id: u32) -> Result<()>;
 
-    async fn alter_source_with_sr(&self, source: PbSource) -> Result<()>;
+    /// Replace the source in the catalog.
+    async fn alter_source(&self, source: PbSource) -> Result<()>;
 
     async fn alter_parallelism(
         &self,
@@ -299,11 +296,6 @@ impl CatalogWriter for CatalogWriterImpl {
         self.wait_version(version).await
     }
 
-    async fn alter_source_column(&self, source: PbSource) -> Result<()> {
-        let version = self.meta_client.alter_source_column(source).await?;
-        self.wait_version(version).await
-    }
-
     async fn replace_table(
         &self,
         source: Option<PbSource>,
@@ -319,20 +311,12 @@ impl CatalogWriter for CatalogWriterImpl {
         self.wait_version(version).await
     }
 
-    async fn create_source(&self, source: PbSource) -> Result<()> {
-        let version = self.meta_client.create_source(source).await?;
-        self.wait_version(version).await
-    }
-
-    async fn create_source_with_graph(
+    async fn create_source(
         &self,
         source: PbSource,
-        graph: StreamFragmentGraph,
+        graph: Option<StreamFragmentGraph>,
     ) -> Result<()> {
-        let version = self
-            .meta_client
-            .create_source_with_graph(source, graph)
-            .await?;
+        let version = self.meta_client.create_source(source, graph).await?;
         self.wait_version(version).await
     }
 
@@ -573,8 +557,8 @@ impl CatalogWriter for CatalogWriterImpl {
         self.wait_version(version).await
     }
 
-    async fn alter_source_with_sr(&self, source: PbSource) -> Result<()> {
-        let version = self.meta_client.alter_source_with_sr(source).await?;
+    async fn alter_source(&self, source: PbSource) -> Result<()> {
+        let version = self.meta_client.alter_source(source).await?;
         self.wait_version(version).await
     }
 
diff --git a/src/frontend/src/handler/alter_source_column.rs b/src/frontend/src/handler/alter_source_column.rs
index 43985518fd1b..d7b90a03172d 100644
--- a/src/frontend/src/handler/alter_source_column.rs
+++ b/src/frontend/src/handler/alter_source_column.rs
@@ -82,13 +82,13 @@ pub async fn handle_alter_source_column(
             )
             .into());
         }
-        SourceEncode::Invalid | SourceEncode::Native => {
+        SourceEncode::Invalid | SourceEncode::Native | SourceEncode::None => {
             return Err(RwError::from(ErrorCode::NotSupported(
                 format!("alter source with encode {:?}", encode),
-                "alter source with encode JSON | BYTES | CSV".into(),
+                "Only source with encode JSON | BYTES | CSV | PARQUET can be altered".into(),
             )));
         }
-        _ => {}
+        SourceEncode::Json | SourceEncode::Csv | SourceEncode::Bytes | SourceEncode::Parquet => {}
     }
 
     let columns = &mut catalog.columns;
@@ -117,7 +117,7 @@ pub async fn handle_alter_source_column(
 
     let catalog_writer = session.catalog_writer()?;
     catalog_writer
-        .alter_source_column(catalog.to_prost(schema_id, db_id))
+        .alter_source(catalog.to_prost(schema_id, db_id))
         .await?;
 
     Ok(PgResponse::empty_result(StatementType::ALTER_SOURCE))
diff --git a/src/frontend/src/handler/alter_source_with_sr.rs b/src/frontend/src/handler/alter_source_with_sr.rs
index 01e09b0c4f5f..25de847fca3f 100644
--- a/src/frontend/src/handler/alter_source_with_sr.rs
+++ b/src/frontend/src/handler/alter_source_with_sr.rs
@@ -278,7 +278,7 @@ pub async fn handle_alter_source_with_sr(
     pb_source.version += 1;
 
     let catalog_writer = session.catalog_writer()?;
-    catalog_writer.alter_source_with_sr(pb_source).await?;
+    catalog_writer.alter_source(pb_source).await?;
 
     Ok(RwPgResponse::empty_result(StatementType::ALTER_SOURCE))
 }
diff --git a/src/frontend/src/handler/create_source.rs b/src/frontend/src/handler/create_source.rs
index 7cbf4fbaf47e..aeaa026dffff 100644
--- a/src/frontend/src/handler/create_source.rs
+++ b/src/frontend/src/handler/create_source.rs
@@ -1720,12 +1720,10 @@ pub async fn handle_create_source(
             let stream_plan = source_node.to_stream(&mut ToStreamContext::new(false))?;
             build_graph(stream_plan)?
         };
-        catalog_writer
-            .create_source_with_graph(source, graph)
-            .await?;
+        catalog_writer.create_source(source, Some(graph)).await?;
     } else {
         // For other sources we don't create a streaming job
-        catalog_writer.create_source(source).await?;
+        catalog_writer.create_source(source, None).await?;
     }
 
     Ok(PgResponse::empty_result(StatementType::CREATE_SOURCE))
diff --git a/src/frontend/src/test_utils.rs b/src/frontend/src/test_utils.rs
index 612388926215..7826890c84d1 100644
--- a/src/frontend/src/test_utils.rs
+++ b/src/frontend/src/test_utils.rs
@@ -318,14 +318,10 @@ impl CatalogWriter for MockCatalogWriter {
         Ok(())
     }
 
-    async fn create_source(&self, source: PbSource) -> Result<()> {
-        self.create_source_inner(source).map(|_| ())
-    }
-
-    async fn create_source_with_graph(
+    async fn create_source(
         &self,
         source: PbSource,
-        _graph: StreamFragmentGraph,
+        _graph: Option<StreamFragmentGraph>,
     ) -> Result<()> {
         self.create_source_inner(source).map(|_| ())
     }
@@ -569,12 +565,7 @@ impl CatalogWriter for MockCatalogWriter {
         Ok(())
     }
 
-    async fn alter_source_column(&self, source: PbSource) -> Result<()> {
-        self.catalog.write().update_source(&source);
-        Ok(())
-    }
-
-    async fn alter_source_with_sr(&self, source: PbSource) -> Result<()> {
+    async fn alter_source(&self, source: PbSource) -> Result<()> {
         self.catalog.write().update_source(&source);
         Ok(())
     }
diff --git a/src/meta/service/src/ddl_service.rs b/src/meta/service/src/ddl_service.rs
index 641bc392f722..de9485ab3e12 100644
--- a/src/meta/service/src/ddl_service.rs
+++ b/src/meta/service/src/ddl_service.rs
@@ -240,7 +240,7 @@ impl DdlService for DdlServiceImpl {
             None => {
                 let version = self
                     .ddl_controller
-                    .run_command(DdlCommand::CreateSource(source))
+                    .run_command(DdlCommand::CreateSourceWithoutStreamingJob(source))
                     .await?;
                 Ok(Response::new(CreateSourceResponse {
                     status: None,
@@ -695,6 +695,7 @@ impl DdlService for DdlServiceImpl {
         }))
     }
 
+    /// Only support add column for now.
     async fn alter_source(
         &self,
         request: Request<AlterSourceRequest>,
diff --git a/src/meta/src/controller/catalog.rs b/src/meta/src/controller/catalog.rs
index 11fe99771a4b..f747100eaed8 100644
--- a/src/meta/src/controller/catalog.rs
+++ b/src/meta/src/controller/catalog.rs
@@ -2607,10 +2607,7 @@ impl CatalogController {
             .collect())
     }
 
-    pub async fn alter_source_column(
-        &self,
-        pb_source: PbSource,
-    ) -> MetaResult<NotificationVersion> {
+    pub async fn alter_source(&self, pb_source: PbSource) -> MetaResult<NotificationVersion> {
         let source_id = pb_source.id as SourceId;
         let inner = self.inner.write().await;
         let txn = inner.db.begin().await?;
diff --git a/src/meta/src/manager/catalog/mod.rs b/src/meta/src/manager/catalog/mod.rs
index d139ec8e037c..773428beb9e6 100644
--- a/src/meta/src/manager/catalog/mod.rs
+++ b/src/meta/src/manager/catalog/mod.rs
@@ -2632,7 +2632,7 @@ impl CatalogManager {
         Ok(version)
     }
 
-    pub async fn alter_source_column(&self, source: Source) -> MetaResult<NotificationVersion> {
+    pub async fn alter_source(&self, source: Source) -> MetaResult<NotificationVersion> {
         let source_id = source.get_id();
         let core = &mut *self.core.lock().await;
         let database_core = &mut core.database;
diff --git a/src/meta/src/rpc/ddl_controller.rs b/src/meta/src/rpc/ddl_controller.rs
index 4c1988a37d44..43c8b52a571c 100644
--- a/src/meta/src/rpc/ddl_controller.rs
+++ b/src/meta/src/rpc/ddl_controller.rs
@@ -131,7 +131,7 @@ pub enum DdlCommand {
     DropDatabase(DatabaseId),
     CreateSchema(Schema),
     DropSchema(SchemaId),
-    CreateSource(Source),
+    CreateSourceWithoutStreamingJob(Source),
     DropSource(SourceId, DropMode),
     CreateFunction(Function),
     DropFunction(FunctionId),
@@ -289,7 +289,9 @@ impl DdlController {
                 DdlCommand::DropDatabase(database_id) => ctrl.drop_database(database_id).await,
                 DdlCommand::CreateSchema(schema) => ctrl.create_schema(schema).await,
                 DdlCommand::DropSchema(schema_id) => ctrl.drop_schema(schema_id).await,
-                DdlCommand::CreateSource(source) => ctrl.create_source(source).await,
+                DdlCommand::CreateSourceWithoutStreamingJob(source) => {
+                    ctrl.create_source_without_streaming_job(source).await
+                }
                 DdlCommand::DropSource(source_id, drop_mode) => {
                     ctrl.drop_source(source_id, drop_mode).await
                 }
@@ -340,7 +342,7 @@ impl DdlController {
                 }
                 DdlCommand::CreateSecret(secret) => ctrl.create_secret(secret).await,
                 DdlCommand::DropSecret(secret_id) => ctrl.drop_secret(secret_id).await,
-                DdlCommand::AlterSourceColumn(source) => ctrl.alter_source_column(source).await,
+                DdlCommand::AlterSourceColumn(source) => ctrl.alter_source(source).await,
                 DdlCommand::CommentOn(comment) => ctrl.comment_on(comment).await,
                 DdlCommand::CreateSubscription(subscription) => {
                     ctrl.create_subscription(subscription).await
@@ -458,7 +460,11 @@ impl DdlController {
         }
     }
 
-    async fn create_source(&self, mut source: Source) -> MetaResult<NotificationVersion> {
+    /// Shared source is handled in [`Self::create_streaming_job`]
+    async fn create_source_without_streaming_job(
+        &self,
+        mut source: Source,
+    ) -> MetaResult<NotificationVersion> {
         match &self.metadata_manager {
             MetadataManager::V1(mgr) => {
                 source.id = self.gen_unique_id::<{ IdCategory::Table }>().await?;
@@ -523,11 +529,12 @@ impl DdlController {
         Ok(version)
     }
 
-    // Maybe we can unify `alter_source_column` and `alter_source_name`.
-    async fn alter_source_column(&self, source: Source) -> MetaResult<NotificationVersion> {
+    /// This replaces the source in the catalog.
+    /// Note: `StreamSourceInfo` in downstream MVs' `SourceExecutor`s are not updated.
+    async fn alter_source(&self, source: Source) -> MetaResult<NotificationVersion> {
         match &self.metadata_manager {
-            MetadataManager::V1(mgr) => mgr.catalog_manager.alter_source_column(source).await,
-            MetadataManager::V2(mgr) => mgr.catalog_controller.alter_source_column(source).await,
+            MetadataManager::V1(mgr) => mgr.catalog_manager.alter_source(source).await,
+            MetadataManager::V2(mgr) => mgr.catalog_controller.alter_source(source).await,
         }
     }
 
diff --git a/src/rpc_client/src/meta_client.rs b/src/rpc_client/src/meta_client.rs
index 67ea55269b2b..a226e4d67249 100644
--- a/src/rpc_client/src/meta_client.rs
+++ b/src/rpc_client/src/meta_client.rs
@@ -410,24 +410,14 @@ impl MetaClient {
         Ok(resp.version)
     }
 
-    pub async fn create_source(&self, source: PbSource) -> Result<CatalogVersion> {
-        let request = CreateSourceRequest {
-            source: Some(source),
-            fragment_graph: None,
-        };
-
-        let resp = self.inner.create_source(request).await?;
-        Ok(resp.version)
-    }
-
-    pub async fn create_source_with_graph(
+    pub async fn create_source(
         &self,
         source: PbSource,
-        graph: StreamFragmentGraph,
+        graph: Option<StreamFragmentGraph>,
     ) -> Result<CatalogVersion> {
         let request = CreateSourceRequest {
             source: Some(source),
-            fragment_graph: Some(graph),
+            fragment_graph: graph,
         };
 
         let resp = self.inner.create_source(request).await?;
@@ -509,15 +499,6 @@ impl MetaClient {
         Ok(resp.version)
     }
 
-    // only adding columns is supported
-    pub async fn alter_source_column(&self, source: PbSource) -> Result<CatalogVersion> {
-        let request = AlterSourceRequest {
-            source: Some(source),
-        };
-        let resp = self.inner.alter_source(request).await?;
-        Ok(resp.version)
-    }
-
     pub async fn alter_owner(&self, object: Object, owner_id: u32) -> Result<CatalogVersion> {
         let request = AlterOwnerRequest {
             object: Some(object),
@@ -540,7 +521,7 @@ impl MetaClient {
         Ok(resp.version)
     }
 
-    pub async fn alter_source_with_sr(&self, source: PbSource) -> Result<CatalogVersion> {
+    pub async fn alter_source(&self, source: PbSource) -> Result<CatalogVersion> {
         let request = AlterSourceRequest {
             source: Some(source),
         };
diff --git a/src/sqlparser/src/ast/statement.rs b/src/sqlparser/src/ast/statement.rs
index b8e1aa245b4e..7dd7564fc666 100644
--- a/src/sqlparser/src/ast/statement.rs
+++ b/src/sqlparser/src/ast/statement.rs
@@ -219,6 +219,7 @@ impl Encode {
     }
 }
 
+/// `FORMAT ... ENCODE ... [(a=b, ...)] [KEY ENCODE ...]`
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct ConnectorSchema {
diff --git a/src/stream/src/executor/source/source_backfill_executor.rs b/src/stream/src/executor/source/source_backfill_executor.rs
index 3f2cd83aca28..77cdc90e546f 100644
--- a/src/stream/src/executor/source/source_backfill_executor.rs
+++ b/src/stream/src/executor/source/source_backfill_executor.rs
@@ -580,7 +580,7 @@ impl<S: StateStore> SourceBackfillExecutorInner<S> {
                                     // Currently, `CreateMviewProgress` is designed for MV backfill, and rw_ddl_progress calculates
                                     // progress based on the number of consumed rows and an estimated total number of rows from hummock.
                                     // For now, we just rely on the same code path, and for source backfill, the progress will always be 99.99%.
-                                    tracing::info!("progress finish");
+                                    tracing::debug!("progress finish");
                                     let epoch = barrier.epoch;
                                     self.progress.finish(epoch, 114514);
                                     // yield barrier after reporting progress