From 34db0daf1f1d55bcd0f7ec1c9ff780b5b89d7d4c Mon Sep 17 00:00:00 2001
From: "vitess-bot[bot]" <108069721+vitess-bot[bot]@users.noreply.github.com>
Date: Mon, 27 Nov 2023 10:23:18 -0600
Subject: [PATCH] [release-18.0] evalengine: Fix the min / max calculation for
 decimals (#14614) (#14616)

Co-authored-by: vitess-bot[bot] <108069721+vitess-bot[bot]@users.noreply.github.com>
---
 go/vt/vtgate/evalengine/api_aggregation.go      | 2 ++
 go/vt/vtgate/evalengine/api_aggregation_test.go | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/go/vt/vtgate/evalengine/api_aggregation.go b/go/vt/vtgate/evalengine/api_aggregation.go
index c0d490ced22..05a4f8711ad 100644
--- a/go/vt/vtgate/evalengine/api_aggregation.go
+++ b/go/vt/vtgate/evalengine/api_aggregation.go
@@ -389,6 +389,7 @@ func (s *aggregationDecimal) Min(value sqltypes.Value) error {
 	}
 	if !s.dec.IsInitialized() || dec.Cmp(s.dec) < 0 {
 		s.dec = dec
+		s.prec = -dec.Exponent()
 	}
 	return nil
 }
@@ -403,6 +404,7 @@ func (s *aggregationDecimal) Max(value sqltypes.Value) error {
 	}
 	if !s.dec.IsInitialized() || dec.Cmp(s.dec) > 0 {
 		s.dec = dec
+		s.prec = -dec.Exponent()
 	}
 	return nil
 }
diff --git a/go/vt/vtgate/evalengine/api_aggregation_test.go b/go/vt/vtgate/evalengine/api_aggregation_test.go
index aab49541e71..bd3a10547fe 100644
--- a/go/vt/vtgate/evalengine/api_aggregation_test.go
+++ b/go/vt/vtgate/evalengine/api_aggregation_test.go
@@ -72,6 +72,12 @@ func TestMinMax(t *testing.T) {
 			min:    sqltypes.NewVarBinary("a"),
 			max:    sqltypes.NewVarBinary("b"),
 		},
+		{
+			type_:  sqltypes.Decimal,
+			values: []sqltypes.Value{sqltypes.NewDecimal("1.001"), sqltypes.NewDecimal("2.1")},
+			min:    sqltypes.NewDecimal("1.001"),
+			max:    sqltypes.NewDecimal("2.1"),
+		},
 		{
 			// accent insensitive
 			type_: sqltypes.VarChar,