rewrite yield clause

vesoft-inc · Nov 11, 2021 · fa692a9 · fa692a9
1 parent cfbd4bb
commit fa692a9
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Showing 4 changed files with 31 additions and 28 deletions.
diff --git a/src/common/expression/LabelTagPropertyExpression.cpp b/src/common/expression/LabelTagPropertyExpression.cpp
@@ -1,7 +1,6 @@
 /* Copyright (c) 2021 vesoft inc. All rights reserved.
  *
- * This source code is licensed under Apache 2.0 License,
- * attached with Common Clause Condition 1.0, found in the LICENSES directory.
+ * This source code is licensed under Apache 2.0 License.
  */
 #include "common/expression/LabelTagPropertyExpression.h"
 
@@ -10,7 +9,7 @@
 namespace nebula {
 
 const Value& LabelTagPropertyExpression::eval(ExpressionContext& ctx) {
-  const auto& var = ctx.getVar(label_);
+  const auto& var = label_->eval(ctx);
   if (var.type() != Value::Type::VERTEX) {
     return Value::kNullBadType;
   }
@@ -26,26 +25,27 @@ const Value& LabelTagPropertyExpression::eval(ExpressionContext& ctx) {
 }
 
 std::string LabelTagPropertyExpression::toString() const {
-  return label_ + "." + tag_ + "." + prop_;
+  std::string labelStr = label_->toString();
+  return labelStr.erase(0, 1) + "." + tag_ + "." + prop_;
 }
 
 bool LabelTagPropertyExpression::operator==(const Expression& rhs) const {
   if (kind_ != rhs.kind()) {
     return false;
   }
   const auto& expr = static_cast<const LabelTagPropertyExpression&>(rhs);
-  return label_ == expr.label_ && tag_ == expr.tag_ && prop_ == expr.prop_;
+  return *label_ == *expr.label_ && tag_ == expr.tag_ && prop_ == expr.prop_;
 }
 
 void LabelTagPropertyExpression::writeTo(Encoder& encoder) const {
   encoder << kind_;
-  encoder << label_;
+  encoder << *label_;
   encoder << tag_;
   encoder << prop_;
 }
 
 void LabelTagPropertyExpression::resetFrom(Decoder& decoder) {
-  label_ = decoder.readStr();
+  label_ = decoder.readExpression(pool_);
   tag_ = decoder.readStr();
   prop_ = decoder.readStr();
 }

diff --git a/src/common/expression/LabelTagPropertyExpression.h b/src/common/expression/LabelTagPropertyExpression.h
@@ -1,7 +1,6 @@
 /* Copyright (c) 2021 vesoft inc. All rights reserved.
  *
- * This source code is licensed under Apache 2.0 License,
- * attached with Common Clause Condition 1.0, found in the LICENSES directory.
+ * This source code is licensed under Apache 2.0 License.
  */
 
 #pragma once
@@ -22,7 +21,7 @@ class LabelTagPropertyExpression final : public Expression {
   LabelTagPropertyExpression& operator=(LabelTagPropertyExpression&&) = delete;
 
   static LabelTagPropertyExpression* make(ObjectPool* pool,
-                                          const std::string& label = "",
+                                          Expression* label = nullptr,
                                           const std::string& tag = "",
                                           const std::string& prop = "") {
     return pool->add(new LabelTagPropertyExpression(pool, label, tag, prop));
@@ -44,11 +43,11 @@ class LabelTagPropertyExpression final : public Expression {
 
   const std::string& tag() const { return tag_; }
 
-  const std::string& label() const { return label_; }
+  const Expression* label() const { return label_; }
 
  private:
   LabelTagPropertyExpression(ObjectPool* pool,
-                             const std::string& label = "",
+                             Expression* label = nullptr,
                              const std::string& tag = "",
                              const std::string& prop = "")
       : Expression(pool, Kind::kLabelTagProperty), label_(label), tag_(tag), prop_(prop) {}
@@ -57,7 +56,7 @@ class LabelTagPropertyExpression final : public Expression {
   void resetFrom(Decoder& decoder) override;
 
  private:
-  std::string label_;
+  Expression* label_{nullptr};
   std::string tag_;
   std::string prop_;
 };

diff --git a/src/graph/util/ExpressionUtils.cpp b/src/graph/util/ExpressionUtils.cpp
@@ -114,7 +114,7 @@ Expression *ExpressionUtils::rewriteAttr2LabelTagProp(const Expression *expr) {
     if (e->kind() == Expression::Kind::kAttribute) {
       auto attrExpr = static_cast<const AttributeExpression *>(e);
       if (attrExpr->left()->kind() == Expression::Kind::kLabelAttribute &&
-          attrExpr->right()->kind() == Expression::Kind::kLabel) {
+          attrExpr->right()->kind() == Expression::Kind::kConstant) {
         return true;
       }
     }
@@ -128,10 +128,11 @@ Expression *ExpressionUtils::rewriteAttr2LabelTagProp(const Expression *expr) {
     auto tagExpr = const_cast<ConstantExpression *>(labelAttrExpr->right());
     auto propExpr = static_cast<const LabelExpression *>(attrExpr->right());
     QueryExpressionContext ctx(nullptr);
-    const auto &label = labelExpr->eval(ctx);
+    const auto &labelVal = labelExpr->eval(ctx);
+    auto label = VariablePropertyExpression::make(pool, "", labelVal.getStr());
     const auto &tag = tagExpr->eval(ctx);
     const auto &prop = const_cast<LabelExpression *>(propExpr)->eval(ctx);
-    return LabelTagPropertyExpression::make(pool, label.getStr(), tag.getStr(), prop.getStr());
+    return LabelTagPropertyExpression::make(pool, label, tag.getStr(), prop.getStr());
   };
 
   return RewriteVisitor::transform(expr, std::move(matcher), std::move(rewriter));

diff --git a/src/graph/validator/MatchValidator.cpp b/src/graph/validator/MatchValidator.cpp
@@ -349,30 +349,28 @@ Status MatchValidator::validateReturn(MatchReturn *ret,
       return Status::SemanticError("RETURN * is not allowed when there are no variables in scope");
     }
   }
+  std::vector<const Expression *> exprs;
   if (ret->returnItems()->columns()) {
+    exprs.reserve(ret->returnItems()->columns()->size());
     for (auto *column : ret->returnItems()->columns()->columns()) {
       if (ExpressionUtils::hasAny(column->expr(),
                                   {Expression::Kind::kVertex, Expression::Kind::kEdge})) {
         return Status::SemanticError(
             "keywords: vertex and edge are not supported in return clause `%s'",
             column->toString().c_str());
       }
+      if (!retClauseCtx.yield->hasAgg_ &&
+          ExpressionUtils::hasAny(column->expr(), {Expression::Kind::kAggregate})) {
+        retClauseCtx.yield->hasAgg_ = true;
+      }
+      column->setExpr(ExpressionUtils::rewriteAttr2LabelTagProp(column->expr()));
+      exprs.push_back(column->expr());
       columns->addColumn(column->clone().release());
     }
   }
   DCHECK(!columns->empty());
   retClauseCtx.yield->yieldColumns = columns;
 
-  // Check all referencing expressions are valid
-  std::vector<const Expression *> exprs;
-  exprs.reserve(retClauseCtx.yield->yieldColumns->size());
-  for (auto *col : retClauseCtx.yield->yieldColumns->columns()) {
-    if (!retClauseCtx.yield->hasAgg_ &&
-        ExpressionUtils::hasAny(col->expr(), {Expression::Kind::kAggregate})) {
-      retClauseCtx.yield->hasAgg_ = true;
-    }
-    exprs.push_back(col->expr());
-  }
   NG_RETURN_IF_ERROR(validateAliases(exprs, retClauseCtx.yield->aliasesUsed));
   NG_RETURN_IF_ERROR(validateYield(*retClauseCtx.yield));
 
@@ -772,18 +770,23 @@ Status MatchValidator::checkAlias(
       return Status::OK();
     }
     case Expression::Kind::kLabelTagProperty: {
-      auto name = static_cast<const LabelTagPropertyExpression *>(refExpr)->label();
+      auto labelExpr = static_cast<const LabelTagPropertyExpression *>(refExpr)->label();
+      auto name = static_cast<const VariablePropertyExpression *>(labelExpr)->prop();
       auto res = getAliasType(aliasesUsed, name);
       NG_RETURN_IF_ERROR(res);
       if (res.value() != AliasType::kNode) {
-        return Status::SemanticError("Alias: %s 's type must be vertex", name.c_str());
+        return Status::SemanticError("The type of `%s' must be tag", name.c_str());
       }
       return Status::OK();
     }
     case Expression::Kind::kLabelAttribute: {
       auto name = static_cast<const LabelAttributeExpression *>(refExpr)->left()->name();
       auto res = getAliasType(aliasesUsed, name);
       NG_RETURN_IF_ERROR(res);
+      if (res.value() == AliasType::kNode) {
+        return Status::SemanticError(
+            "To get the attribute of the vertex, use alias.tagname.propname format");
+      }
       return Status::OK();
     }
     case Expression::Kind::kEdgeSrc: {