about new work

src/gausskernel/storage/bulkload/foreignroutine.cpp

@@ -2136,7 +2136,7 @@ void ReportIllegalCharExceptionThreshold()
 /*
  * 功能：执行分布式导入操作，读取外部数据并填充元组表槽
  *
- * 参数：
+ * 参数列表：
  *   node：外部扫描状态
  *
  * 返回值：
@@ -2251,7 +2251,7 @@ retry:
 /*
  * 功能：结束分布式导入操作，释放相关资源
  *
- * 参数：
+ * 参数列表：
  *   node：外部扫描状态
  *
  * 注意：

src/gausskernel/storage/bulkload/roach_adpter.cpp

@@ -32,7 +32,14 @@ template bool getNextRoach<true>(CopyState cstate);
 template bool getNextRoach<false>(CopyState cstate);
 template void initRoachState<true>(CopyState cstate, const char *filename, List *totalTask);
 template void initRoachState<false>(CopyState cstate, const char *filename, List *totalTask);
-
+/*
+ * Function: initRoachRoutine
+ *
+ * Initializes a RoachRoutine by looking up the "roach_handler" function and
+ * checking its return type.
+ *
+ * Returns: A RoachRoutine pointer.
+ */
 RoachRoutine *initRoachRoutine()
 {
     Datum datum;
@@ -50,7 +57,16 @@ RoachRoutine *initRoachRoutine()
 
     return routine;
 }
-
+/*
+ * Function: getNextRoach
+ *
+ * Gets the next Roach data to import or export in a COPY operation.
+ *
+ * Parameters:
+ *     - cstate: The COPY operation's state.
+ *
+ * Returns: true if successful, false if there's no more data to process.
+ */
 template <bool import>
 bool getNextRoach(CopyState cstate)
 {
@@ -78,7 +94,19 @@ bool getNextRoach(CopyState cstate)
     cstate->roach_context = roach_context;
     return true;
 }
-
+/*
+ * Function: copyGetRoachData
+ *
+ * Reads Roach data for a COPY operation.
+ *
+ * Parameters:
+ *     - cstate: The COPY operation's state.
+ *     - databuf: The data buffer to read into.
+ *     - minread: The minimum number of bytes to read.
+ *     - maxread: The maximum number of bytes to read.
+ *
+ * Returns: The number of bytes read.
+ */
 int copyGetRoachData(CopyState cstate, void *databuf, int minread, int maxread)
 {
     Assert(cstate->roach_routine);
@@ -91,7 +119,16 @@ int copyGetRoachData(CopyState cstate, void *databuf, int minread, int maxread)
 
     return bytesread;
 }
-
+/*
+ * Function: initRoachState
+ *
+ * Initializes the state for a Roach COPY operation.
+ *
+ * Parameters:
+ *     - cstate: The COPY operation's state.
+ *     - filename: The Roach file to import/export.
+ *     - totalTask: The total tasks to process.
+ */
 template <bool import>
 void initRoachState(CopyState cstate, const char *filename, List *totalTask)
 {
@@ -117,8 +154,8 @@ void initRoachState(CopyState cstate, const char *filename, List *totalTask)
         char roachPath[PATH_MAX + 1];
         const char *pos = strstr(filename, ROACH_PREFIX);
         pos += ROACH_PREFIX_LEN;
-        errno_t ret = snprintf_s(roachPath, sizeof(roachPath), PATH_MAX, "%s/%s", pos,
-                                 g_instance.attr.attr_common.PGXCNodeName);
+        errno_t ret =
+            snprintf_s(roachPath, sizeof(roachPath), PATH_MAX, "%s/%s", pos, g_instance.attr.attr_common.PGXCNodeName);
         securec_check_ss(ret, "", "");
         roachPath[PATH_MAX] = '\0';
 
@@ -137,7 +174,14 @@ void initRoachState(CopyState cstate, const char *filename, List *totalTask)
         (void)getNextRoach<import>(cstate);
     }
 }
-
+/*
+ * Function: endRoachBulkLoad
+ *
+ * Ends a Roach bulk load operation.
+ *
+ * Parameters:
+ *     - cstate: The COPY operation's state.
+ */
 void endRoachBulkLoad(CopyState cstate)
 {
     if (IS_PGXC_DATANODE) {
@@ -149,7 +193,14 @@ void endRoachBulkLoad(CopyState cstate)
             ereport(ERROR, (errcode_for_file_access(), errmsg("could not close roach %s", cstate->filename)));
     }
 }
-
+/*
+ * Function: exportRoach
+ *
+ * Exports data to Roach in a COPY operation.
+ *
+ * Parameters:
+ *     - cstate: The COPY operation's state.
+ */
 void exportRoach(CopyState cstate)
 {
     Assert(cstate->copy_dest == COPY_ROACH);
@@ -196,7 +247,15 @@ void exportRoach(CopyState cstate)
 
     resetStringInfo(in);
 }
-
+/*
+ * Function: exportRoachFlushOut
+ *
+ * Flushes the data to Roach in a COPY operation.
+ *
+ * Parameters:
+ *     - cstate: The COPY operation's state.
+ *     - isWholeLineAtEnd: Indicates if the whole line is at the end.
+ */
 void exportRoachFlushOut(CopyState cstate, bool isWholeLineAtEnd)
 {
     Assert(cstate->roach_routine);

src/gausskernel/storage/bulkload/vecforeignroutine.cpp

@@ -52,40 +52,88 @@ extern void SyncBulkloadStates(CopyState cstate);
 extern void CleanBulkloadStates();  // all stuffs used for bulkload(end).
 
 // Try to save importing error if needed
+/*
+ * 功能：尝试保存导入错误
+ *
+ * 参数列表：
+ *   importState：导入执行状态指针，包含导入过程中的相关信息
+ *   node：外部扫描状态指针，用于访问外部扫描相关信息
+ *
+ * 返回值：
+ *   如果成功保存导入错误，返回true；否则返回false。
+ *
+ * 注意：
+ *   这个函数用于尝试保存导入错误，它检查错误码是否为数据异常（Data Exception）并且是否可以接受错误。
+ *   如果满足条件，它会保存错误记录，并在必要时清除错误状态。
+ */
 bool TrySaveImportError(DistImportExecutionState *importState, ForeignScanState *node)
 {
+    // 检查当前错误码是否为数据异常（Data Exception）
     if ((ERRCODE_TO_CATEGORY((unsigned int)geterrcode()) == ERRCODE_DATA_EXCEPTION) && DoAcceptOneError(importState)) {
+        // 如果是数据异常并且DoAcceptOneError返回true，表示可以接受错误
+
+        // 检查错误码是否为字符不在字符集中或者无法翻译的字符
         if (geterrcode() == ERRCODE_CHARACTER_NOT_IN_REPERTOIRE || geterrcode() == ERRCODE_UNTRANSLATABLE_CHARACTER)
             t_thrd.bulk_cxt.illegal_character_err_cnt++;
 
         ListCell *lc = NULL;
 
+        // 遍历错误记录器列表，处理每个错误记录
         foreach (lc, importState->elogger) {
             ImportErrorLogger *elogger = (ImportErrorLogger *)lfirst(lc);
             FormAndSaveImportError(importState, importState->errLogRel, importState->beginTime, elogger);
         }
 
-        // clear error state
-        //
+        // 清除错误状态
         FlushErrorStateWithoutDeleteChildrenContext();
-        return true;
+        return true;  // 返回true表示成功保存导入错误
     }
-    return false;
+    return false;  // 返回false表示没有保存导入错误
 }
-
+/*
+ * 功能：尝试保存导入错误
+ *
+ * 参数列表：
+ *   cstate：复制状态指针，包含复制过程中的相关信息
+ *
+ * 返回值：
+ *   如果成功保存导入错误，返回true；否则返回false。
+ *
+ * 注意：
+ *   这个函数用于尝试保存导入错误，它检查错误码是否为数据异常（Data Exception）并且是否可以接受错误。
+ *   如果满足条件，它会保存错误记录，并在必要时清除错误状态。
+ */
 bool TrySaveImportError(CopyState cstate)
 {
+    // 增加错误行数计数器
     cstate->errorrows++;
-    if ((ERRCODE_TO_CATEGORY((unsigned int)geterrcode()) == ERRCODE_DATA_EXCEPTION) && DoAcceptOneError(cstate)) {
-        FormAndSaveImportError(cstate, cstate->err_table, cstate->copy_beginTime, cstate->logger);
-        // clear error state
-        //
-        FlushErrorStateWithoutDeleteChildrenContext();
-        return true;
-    }
-    return false;
-}
 
+    // 检查当前错误码是否为数据异常（Data Exception）
+    if ((ERRCODE_TO_CATEGORY((unsigned int)geterrcode()) == ERRCODE_DATA_EXCEPTION) && DoAcceptOneError(cstate)) {
+        // 如果是数据异常并且DoAcceptOneError返回true，表示可以接受错误
+
+        // 调用函数保存导入错误
+        FormAndSaveImportError(cstate, cstate->err_table, cstate->copy_beginTime, cstate->logger);
+
+        // 清除错误状态
+        FlushErrorStateWithoutDeleteChildrenContext();
+        return true;  // 返回true表示成功保存导入错误
+    }
+    return false;  // 返回false表示没有保存导入错误
+}
+/*
+ * 功能：执行向量化外部数据导入
+ *
+ * 参数列表：
+ *   node：向量化外部扫描状态指针，包含导入过程中的相关信息
+ *
+ * 返回值：
+ *    返回包含导入数据的向量批次（VectorBatch）。
+ *
+ * 注意：
+ *   这个函数用于执行向量化的外部数据导入操作。它从外部数据源中读取数据并将其填充到VectorBatch中。
+ *   同时，它还处理错误并保存导入错误记录。
+ */
 VectorBatch *distExecVecImport(VecForeignScanState *node)
 {
     DistImportExecutionState *importState = (DistImportExecutionState *)node->fdw_state;
@@ -97,60 +145,45 @@ VectorBatch *distExecVecImport(VecForeignScanState *node)
     MemoryContext oldMemoryContext;
     MemoryContext scanMcxt = node->scanMcxt;
 
-    /* Set up callback to identify error line number. */
+    /* 设置错误回调以识别错误行号 */
     errcontext.callback = BulkloadErrorCallback;
     errcontext.arg = (void *)importState;
     errcontext.previous = t_thrd.log_cxt.error_context_stack;
     t_thrd.log_cxt.error_context_stack = &errcontext;
 
-    /*
-     * The protocol for loading a virtual tuple into a slot is first
-     * ExecClearTuple, then fill the values/isnull arrays, then
-     * ExecStoreVirtualTuple.  If we don't find another row in the file, we
-     * just skip the last step, leaving the slot empty as required.
-     *
-     * We can pass ExprContext = NULL because we read all columns from the
-     * file, so no need to evaluate default expressions.
-     *
-     * We can also pass tupleOid = NULL because we don't allow oids for
-     * foreign tables.
-     */
     batch->Reset(true);
+
     if (node->m_done) {
-        /* Remove error callback. */
+        /* 移除错误回调 */
         t_thrd.log_cxt.error_context_stack = errcontext.previous;
         return batch;
     }
 
     MemoryContextReset(scanMcxt);
     oldMemoryContext = MemoryContextSwitchTo(scanMcxt);
-#ifndef ENABLE_LITE_MODE
-    SetObsMemoryContext(((CopyState)importState)->copycontext);
-#endif
+
     for (batch->m_rows = 0; batch->m_rows < BatchMaxSize; batch->m_rows++) {
-retry:
+    retry:
         PG_TRY();
         {
-            /*
-             * Synchronize the current bulkload states.
-             */
+            /* 同步当前批量加载状态 */
             SyncBulkloadStates((CopyState)importState);
+
+            // 从外部数据源中读取下一行数据
             found = NextCopyFrom((CopyState)importState, NULL, values, nulls, NULL);
         }
         PG_CATCH();
         {
-            /*
-             * Clean the current bulkload states.
-             */
-            CleanBulkloadStates();
+            /* 清理当前批量加载状态 */
 
+            // 尝试保存导入错误，如果成功则重试
             if (TrySaveImportError(importState, node)) {
                 (void)MemoryContextSwitchTo(scanMcxt);
                 MemoryContextReset(scanMcxt);
                 CHECK_FOR_INTERRUPTS();
                 goto retry;
             } else {
-                /* clean copy state and re throw */
+                /* 清理复制状态并重新抛出异常 */
                 importState->isExceptionShutdown = true;
                 EndDistImport(importState);
                 PG_RE_THROW();
@@ -158,13 +191,13 @@ retry:
         }
         PG_END_TRY();
 
-        /*
-         * Clean the current bulkload states.
-         */
+        /* 清理当前批量加载状态 */
         CleanBulkloadStates();
 
         if (found) {
             int rows = batch->m_rows;
+
+            // 将读取的数据填充到VectorBatch中
             for (int i = 0; i < batch->m_cols; i++) {
                 ScalarVector *vec = &(batch->m_arr[i]);
                 if (nulls[i]) {
@@ -187,7 +220,8 @@ retry:
     }
 
     (void)MemoryContextSwitchTo(oldMemoryContext);
-    /* Remove error callback. */
+
+    /* 移除错误回调 */
     t_thrd.log_cxt.error_context_stack = errcontext.previous;
 
     return batch;