3 files changed, 63 insertions, 1 deletions
diff --git a/core/vm/sqlvm/checker/cast.go b/core/vm/sqlvm/checker/cast.go
new file mode 100644
index 000000000..40da20f81
--- /dev/null
+++ b/core/vm/sqlvm/checker/cast.go
@@ -0,0 +1,60 @@
+package checker
+
+import (
+	"fmt"
+
+	"github.com/dexon-foundation/dexon/core/vm/sqlvm/ast"
+	"github.com/dexon-foundation/dexon/core/vm/sqlvm/errors"
+	"github.com/dexon-foundation/dexon/core/vm/sqlvm/schema"
+)
+
+func checkCastOperator(n *ast.CastOperatorNode,
+	s schema.Schema, o CheckOptions, c *schemaCache, el *errors.ErrorList,
+	tr schema.TableRef, ta typeAction) ast.ExprNode {
+
+	fn := "CheckCastOperator"
+	op := "operator CAST"
+
+	hasError := false
+
+	source := n.SourceExpr
+	source = checkExpr(source, s, o, c, el, tr, nil)
+	if source != nil {
+		n.SourceExpr = source
+	} else {
+		hasError = true
+	}
+	target := n.TargetType
+	dt, code, message := target.GetType()
+	if code == errors.ErrorCodeNil {
+		if !dt.ValidColumn() {
+			el.Append(errors.Error{
+				Position: target.GetPosition(),
+				Length:   target.GetLength(),
+				Category: errors.ErrorCategorySemantic,
+				Code:     errors.ErrorCodeInvalidCastDataType,
+				Severity: errors.ErrorSeverityError,
+				Prefix:   fn,
+				Message: fmt.Sprintf(
+					"cannot use %s with type %s", op, dt.String()),
+			}, &hasError)
+		}
+	} else {
+		el.Append(errors.Error{
+			Position: target.GetPosition(),
+			Length:   target.GetLength(),
+			Category: errors.ErrorCategorySemantic,
+			Code:     code,
+			Severity: errors.ErrorSeverityError,
+			Prefix:   fn,
+			Message:  message,
+		}, &hasError)
+	}
+
+	if hasError {
+		return nil
+	}
+	r := ast.ExprNode(n)
+
+	return verifyTypeAction(r, fn, dt, el, ta)
+}
diff --git a/core/vm/sqlvm/checker/expr.go b/core/vm/sqlvm/checker/expr.go
index d62f82ede..e31a13d62 100644
--- a/core/vm/sqlvm/checker/expr.go
+++ b/core/vm/sqlvm/checker/expr.go
@@ -138,7 +138,7 @@ func checkExpr(n ast.ExprNode,
 		return checkLikeOperator(n, s, o, c, el, tr, ta)
 
 	case *ast.CastOperatorNode:
-		return n
+		return checkCastOperator(n, s, o, c, el, tr, ta)
 
 	case *ast.InOperatorNode:
 		return checkInOperator(n, s, o, c, el, tr, ta)
diff --git a/core/vm/sqlvm/errors/errors.go b/core/vm/sqlvm/errors/errors.go
index dcc8e6a48..2bbac5b4b 100644
--- a/core/vm/sqlvm/errors/errors.go
+++ b/core/vm/sqlvm/errors/errors.go
@@ -170,6 +170,7 @@ const (
 	ErrorCodeConstantTooLong
 	ErrorCodeNonConstantExpression
 	ErrorCodeInvalidAddressChecksum
+	ErrorCodeInvalidCastDataType
 
 	// Runtime Error
 	ErrorCodeInvalidOperandNum
@@ -229,6 +230,7 @@ var errorCodeMap = [...]string{
 	ErrorCodeConstantTooLong:               "constant too long",
 	ErrorCodeNonConstantExpression:         "non-constant expression",
 	ErrorCodeInvalidAddressChecksum:        "invalid address checksum",
+	ErrorCodeInvalidCastDataType:           "invalid cast data type",
 
 	// Runtime Error
 	ErrorCodeInvalidOperandNum:  "invalid operand number",