diff --git a/src/share/object/ob_obj_cast.cpp b/src/share/object/ob_obj_cast.cpp
index 4db6e90794..a8418d9fff 100644
--- a/src/share/object/ob_obj_cast.cpp
+++ b/src/share/object/ob_obj_cast.cpp
@@ -11230,7 +11230,9 @@ bool cast_supported(const ObObjType orig_type, const ObCollationType orig_cs_typ
   } else if (is_oracle_mode() && (clob_in || ob_is_number_tc(orig_type) || ob_is_int_tc(orig_type)
                                   || ob_is_datetime_tc(orig_type)) && blob_out) {
     bret = false;
-  } else if (is_oracle_mode() && ObTinyIntType == orig_type && ob_is_text_tc(expect_type)) {
+  } else if (is_oracle_mode() &&
+             (ObTinyIntType == orig_type || ObDateTimeType == orig_type) &&
+             ob_is_text_tc(expect_type)) {
     bret = false;
   } else {
     ObObjTypeClass orig_tc = ob_obj_type_class(orig_type);
diff --git a/src/sql/engine/expr/ob_expr.cpp b/src/sql/engine/expr/ob_expr.cpp
index 55020c764e..ab888ff57b 100644
--- a/src/sql/engine/expr/ob_expr.cpp
+++ b/src/sql/engine/expr/ob_expr.cpp
@@ -787,6 +787,9 @@ int eval_assign_question_mark_func(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &
       if (ctx.exec_ctx_.get_physical_plan_ctx()->is_ignore_stmt()) {
         cast_mode = cast_mode | CM_WARN_ON_FAIL | CM_CHARSET_CONVERT_IGNORE_ERR;
       }
+      if ((v.is_blob() || dst_meta.is_blob()) && lib::is_oracle_mode()) {
+        cast_mode |= CM_ENABLE_BLOB_CAST;
+      }
       ObCastCtx cast_ctx(&allocator, &dtc_params, cast_mode, dst_meta.get_collation_type());
       if (OB_FAIL(ObObjCaster::to_type(dst_meta.get_type(), cast_ctx, v, dst_obj))) {
         LOG_WARN("failed to cast obj to dst type", K(ret), K(v), K(dst_meta));
diff --git a/src/sql/engine/expr/ob_expr_cast.cpp b/src/sql/engine/expr/ob_expr_cast.cpp
index cc53d46fb9..ff49271998 100644
--- a/src/sql/engine/expr/ob_expr_cast.cpp
+++ b/src/sql/engine/expr/ob_expr_cast.cpp
@@ -273,22 +273,33 @@ bool ObExprCast::check_cast_allowed(const ObObjType orig_type,
   bool res = true;
   ObObjTypeClass ori_tc = ob_obj_type_class(orig_type);
   ObObjTypeClass expect_tc = ob_obj_type_class(expect_type);
-  if (is_oracle_mode() && is_explicit_cast) {
-    // can't cast lob to other type except char/varchar/nchar/nvarchar2/raw. clob to raw not allowed too.
-    if (ObLobTC == ori_tc || ObTextTC == ori_tc) {
-      if (expect_tc == ObJsonTC) {
-        /* oracle mode, json text use lob store */
-      } else if (ObStringTC == expect_tc) {
-        // do nothing
-      } else if (ObRawTC == expect_tc) {
-        res = CS_TYPE_BINARY == orig_cs_type;
-      } else {
+  bool is_expect_lob_tc = (ObLobTC == expect_tc || ObTextTC == expect_tc);
+  bool is_ori_lob_tc = (ObLobTC == ori_tc || ObTextTC == ori_tc);
+  if (is_oracle_mode()) {
+    if (is_explicit_cast) {
+      // can't cast lob to other type except char/varchar/nchar/nvarchar2/raw. clob to raw not allowed too.
+      if (is_ori_lob_tc) {
+        if (expect_tc == ObJsonTC) {
+          /* oracle mode, json text use lob store */
+        } else if (ObStringTC == expect_tc) {
+          // do nothing
+        } else if (ObRawTC == expect_tc) {
+          res = CS_TYPE_BINARY == orig_cs_type;
+        } else {
+          res = false;
+        }
+      }
+      // any type to lob type not allowed.
+      if (is_expect_lob_tc) {
         res = false;
       }
-    }
-    // any type to lob type not allowed.
-    if (ObLobTC == expect_tc || ObTextTC == expect_tc) {
-      res = false;
+    } else {
+      // BINARY FLOAT/DOUBLE not allow cast lob whether explicit
+      if (is_ori_lob_tc) {
+        if (expect_tc == ObFloatTC || expect_tc == ObDoubleTC) {
+          res = false;
+        }
+      }
     }
   }
   return res;