From dd4bd3f360f73345bbc6ae997806893a45b6d4bc Mon Sep 17 00:00:00 2001
From: morrySnow <101034200+morrySnow@users.noreply.github.com>
Date: Tue, 28 Feb 2023 17:59:52 +0800
Subject: [PATCH] [enhancement](Nereids) consider string literal coercion when
 search function signature (#17175)

---
 .../expressions/functions/SearchSignature.java     | 11 ++++++++++-
 .../functions/window/RequireTrivialTypes.java      | 14 ++++++--------
 .../doris/nereids/util/TypeCoercionUtils.java      |  2 +-
 3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/SearchSignature.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/SearchSignature.java
index 49ac214e2e..d20aabcc8e 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/SearchSignature.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/SearchSignature.java
@@ -20,8 +20,10 @@ package org.apache.doris.nereids.trees.expressions.functions;
 import org.apache.doris.catalog.FunctionSignature;
 import org.apache.doris.nereids.exceptions.AnalysisException;
 import org.apache.doris.nereids.trees.expressions.Expression;
+import org.apache.doris.nereids.trees.expressions.literal.Literal;
 import org.apache.doris.nereids.types.DataType;
 import org.apache.doris.nereids.types.coercion.AbstractDataType;
+import org.apache.doris.nereids.util.TypeCoercionUtils;
 
 import com.google.common.collect.Lists;
 
@@ -125,7 +127,14 @@ public class SearchSignature {
         int arity = arguments.size();
         for (int i = 0; i < arity; i++) {
             AbstractDataType sigArgType = sig.getArgType(i);
-            AbstractDataType realType = arguments.get(i).getDataType();
+            DataType realType = arguments.get(i).getDataType();
+            // we need to try to do string literal coercion when search signature.
+            // for example, FUNC_A has two signature FUNC_A(datetime) and FUNC_A(string)
+            // if SQL block is `FUNC_A('2020-02-02 00:00:00')`, we should return signature FUNC_A(datetime).
+            if (arguments.get(i).isLiteral() && realType.isStringLikeType() && sigArgType instanceof DataType) {
+                realType = TypeCoercionUtils.characterLiteralTypeCoercion(((Literal) arguments.get(i)).getStringValue(),
+                                (DataType) sigArgType).orElse(arguments.get(i)).getDataType();
+            }
             if (!typePredicate.apply(sigArgType, realType)) {
                 return false;
             }
diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/window/RequireTrivialTypes.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/window/RequireTrivialTypes.java
index 86137d732f..c53d3ae46d 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/window/RequireTrivialTypes.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/window/RequireTrivialTypes.java
@@ -48,6 +48,7 @@ public interface RequireTrivialTypes {
 
     // todo: add JsonBType
     ImmutableList<DataType> trivialTypes = ImmutableList.of(
+            BooleanType.INSTANCE,
             TinyIntType.INSTANCE,
             SmallIntType.INSTANCE,
             IntegerType.INSTANCE,
@@ -56,18 +57,15 @@ public interface RequireTrivialTypes {
             FloatType.INSTANCE,
             DoubleType.INSTANCE,
             DecimalV2Type.SYSTEM_DEFAULT,
-            DecimalV3Type.DEFAULT_DECIMAL32,
-            DecimalV3Type.DEFAULT_DECIMAL64,
-            DecimalV3Type.DEFAULT_DECIMAL128,
-            BooleanType.INSTANCE,
-            VarcharType.INSTANCE,
-            StringType.INSTANCE,
-            CharType.INSTANCE,
+            DecimalV3Type.SYSTEM_DEFAULT,
             DateType.INSTANCE,
             DateTimeType.INSTANCE,
             DateV2Type.INSTANCE,
             DateTimeV2Type.SYSTEM_DEFAULT,
             TimeType.INSTANCE,
-            TimeV2Type.INSTANCE
+            TimeV2Type.INSTANCE,
+            CharType.SYSTEM_DEFAULT,
+            VarcharType.SYSTEM_DEFAULT,
+            StringType.INSTANCE
     );
 }
diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/util/TypeCoercionUtils.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/util/TypeCoercionUtils.java
index 0f75e5537e..8db97eeca1 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/nereids/util/TypeCoercionUtils.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/nereids/util/TypeCoercionUtils.java
@@ -298,7 +298,7 @@ public class TypeCoercionUtils {
      * characterLiteralTypeCoercion.
      */
     @Developing
-    private static Optional<Expression> characterLiteralTypeCoercion(String value, DataType dataType) {
+    public static Optional<Expression> characterLiteralTypeCoercion(String value, DataType dataType) {
         Expression ret = null;
         try {
             if (dataType instanceof BooleanType) {