From 1e66b0c8b7d0b5f8d0c1c74e56286ce660e92594 Mon Sep 17 00:00:00 2001
From: zclllhhjj <zhaochangle@selectdb.com>
Date: Tue, 5 Nov 2024 14:15:12 +0800
Subject: [PATCH] [Optimize](Expr) Opt getting value of VLitreal (#43204)

### What problem does this PR solve?
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Problem Summary:

For `VLiteral`, it only has one value as expected. So no need to use for
loop.

### Check List (For Committer)

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    - [ ] Regression test
    - [ ] Unit Test
    - [ ] Manual test (add detailed scripts or steps below)
    - [x] No need to test or manual test. Explain why:
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        - [ ] Previous test can cover this change.
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    - [ ] Yes. <!-- Explain the behavior change -->

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---
 be/src/vec/exprs/vliteral.cpp | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/be/src/vec/exprs/vliteral.cpp b/be/src/vec/exprs/vliteral.cpp
index 1d02a63321befd..8dcc5e3cb5a1cf 100644
--- a/be/src/vec/exprs/vliteral.cpp
+++ b/be/src/vec/exprs/vliteral.cpp
@@ -76,15 +76,8 @@ Status VLiteral::execute(VExprContext* context, vectorized::Block* block, int* r
 }
 
 std::string VLiteral::value() const {
-    //TODO: dcheck the equality of size with 1. then use string with size to replace the ss.
-    std::stringstream out;
-    for (size_t i = 0; i < _column_ptr->size(); i++) {
-        if (i != 0) {
-            out << ", ";
-        }
-        out << _data_type->to_string(*_column_ptr, i);
-    }
-    return out.str();
+    DCHECK(_column_ptr->size() == 1);
+    return _data_type->to_string(*_column_ptr, 0);
 }
 
 std::string VLiteral::debug_string() const {