feat(tianmu): support 'ALTER TABLE t1 CHARACTER SET = ...' clause. (s…

…toneatom#848)

[summary]
1 add implement in check_if_supported_inplace_alter;
2 add implement in inplace_alter_table;
3 add implement in commit_inplace_alter_table;

storage/tianmu/handler/tianmu_handler.cpp

@@ -1498,9 +1498,15 @@ int TianmuHandler::reset() {
 enum_alter_inplace_result TianmuHandler::check_if_supported_inplace_alter([[maybe_unused]] TABLE *altered_table,
                                                                           Alter_inplace_info *ha_alter_info) {
   DBUG_ENTER(__PRETTY_FUNCTION__);
+
+  if ((ha_alter_info->handler_flags & TIANMU_SUPPORTED_ALTER_TABLE_OPTIONS) &&
+      (ha_alter_info->create_info->used_fields & HA_CREATE_USED_CHARSET)) {
+    DBUG_RETURN(HA_ALTER_INPLACE_EXCLUSIVE_LOCK);
+  }
+
   if ((ha_alter_info->handler_flags & ~TIANMU_SUPPORTED_ALTER_ADD_DROP_ORDER) &&
       (ha_alter_info->handler_flags != TIANMU_SUPPORTED_ALTER_COLUMN_NAME)) {
-    // support alter table column type 
+    // support alter table column type
     if (ha_alter_info->handler_flags & Alter_inplace_info::ALTER_STORED_COLUMN_TYPE)
       DBUG_RETURN(HA_ALTER_INPLACE_NOT_SUPPORTED);
     // support alter table column exceeded length
@@ -1517,13 +1523,16 @@ enum_alter_inplace_result TianmuHandler::check_if_supported_inplace_alter([[mayb
 
 bool TianmuHandler::inplace_alter_table(TABLE *altered_table, Alter_inplace_info *ha_alter_info) {
   try {
-    if (!(ha_alter_info->handler_flags & ~TIANMU_SUPPORTED_ALTER_ADD_DROP_ORDER)) {
+    if ((ha_alter_info->handler_flags & TIANMU_SUPPORTED_ALTER_TABLE_OPTIONS) &&
+        (ha_alter_info->create_info->used_fields & HA_CREATE_USED_CHARSET)) {
+      DBUG_RETURN(false);
+    } else if (!(ha_alter_info->handler_flags & ~TIANMU_SUPPORTED_ALTER_ADD_DROP_ORDER)) {
       std::vector<Field *> v_old(table_share->field, table_share->field + table_share->fields);
       std::vector<Field *> v_new(altered_table->s->field, altered_table->s->field + altered_table->s->fields);
       ha_rcengine_->PrepareAlterTable(table_name_, v_new, v_old, ha_thd());
-      return false;
+      DBUG_RETURN(false);
     } else if (ha_alter_info->handler_flags == TIANMU_SUPPORTED_ALTER_COLUMN_NAME) {
-      return false;
+      DBUG_RETURN(false);
     }
   } catch (std::exception &e) {
     TIANMU_LOG(LogCtl_Level::ERROR, "An exception is caught: %s", e.what());
@@ -1533,21 +1542,25 @@ bool TianmuHandler::inplace_alter_table(TABLE *altered_table, Alter_inplace_info
 
   my_message(static_cast<int>(common::ErrorCode::UNKNOWN_ERROR), "Unable to inplace alter table", MYF(0));
 
-  return true;
+  DBUG_RETURN(true);
 }
 
 bool TianmuHandler::commit_inplace_alter_table([[maybe_unused]] TABLE *altered_table, Alter_inplace_info *ha_alter_info,
                                                bool commit) {
   if (!commit) {
-    TIANMU_LOG(LogCtl_Level::INFO, "Alter table failed : %s%s", table_name_.c_str(), " rollback");
-    return true;
+    TIANMU_LOG(LogCtl_Level::INFO, "Alter table failed : %s%s", m_table_name.c_str(), " rollback");
+    DBUG_RETURN(true);
+  }
+  if ((ha_alter_info->handler_flags & TIANMU_SUPPORTED_ALTER_TABLE_OPTIONS) &&
+      (ha_alter_info->create_info->used_fields & HA_CREATE_USED_CHARSET)) {
+    DBUG_RETURN(false);
   }
   if (ha_alter_info->handler_flags == TIANMU_SUPPORTED_ALTER_COLUMN_NAME) {
-    return false;
+    DBUG_RETURN(false);
   }
   if ((ha_alter_info->handler_flags & ~TIANMU_SUPPORTED_ALTER_ADD_DROP_ORDER)) {
     TIANMU_LOG(LogCtl_Level::INFO, "Altered table not support type %lu", ha_alter_info->handler_flags);
-    return true;
+    DBUG_RETURN(true);
   }
   fs::path tmp_dir(table_name_ + ".tmp");
   fs::path tab_dir(table_name_ + common::TIANMU_EXT);
@@ -1561,12 +1574,14 @@ bool TianmuHandler::commit_inplace_alter_table([[maybe_unused]] TABLE *altered_t
     std::unordered_set<std::string> s;
     for (auto &it : fs::directory_iterator(tab_dir / common::COLUMN_DIR)) {
       auto target = fs::read_symlink(it.path()).string();
-      if (!target.empty()) s.insert(target);
+      if (!target.empty())
+        s.insert(target);
     }
 
     for (auto &it : fs::directory_iterator(bak_dir / common::COLUMN_DIR)) {
       auto target = fs::read_symlink(it.path()).string();
-      if (target.empty()) continue;
+      if (target.empty())
+        continue;
       auto search = s.find(target);
       if (search == s.end()) {
         fs::remove_all(target);
@@ -1578,9 +1593,9 @@ bool TianmuHandler::commit_inplace_alter_table([[maybe_unused]] TABLE *altered_t
     TIANMU_LOG(LogCtl_Level::ERROR, "file system error: %s %s|%s", e.what(), e.path1().string().c_str(),
                e.path2().string().c_str());
     my_message(static_cast<int>(common::ErrorCode::UNKNOWN_ERROR), "Failed to commit alter table", MYF(0));
-    return true;
+    DBUG_RETURN(true);
   }
-  return false;
+  DBUG_RETURN(false);
 }
 /*
  key: mysql format, may be union key, need changed to kvstore key format

storage/tianmu/handler/tianmu_handler.h

@@ -158,6 +158,7 @@ class TianmuHandler final : public handler {
  public:
   static const Alter_inplace_info::HA_ALTER_FLAGS TIANMU_SUPPORTED_ALTER_ADD_DROP_ORDER;
   static const Alter_inplace_info::HA_ALTER_FLAGS TIANMU_SUPPORTED_ALTER_COLUMN_NAME;
+  static const Alter_inplace_info::HA_ALTER_FLAGS TIANMU_SUPPORTED_ALTER_TABLE_OPTIONS;
 
  protected:
   int set_cond_iter();