[Bug](function) fix Could not find function explode_json_array_json_outer

be/src/vec/functions/function_fake.cpp

@@ -50,9 +50,6 @@ struct FunctionFakeBaseImpl {
     }
     static DataTypes get_variadic_argument_types() {
         if constexpr (VARIADIC) {
-            if constexpr (AlwaysNullable) {
-                return {make_nullable(std::make_shared<ReturnType>())};
-            }
             return {std::make_shared<ReturnType>()};
         } else {
             return {};

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/generator/ExplodeJsonArrayJsonOuter.java

@@ -19,7 +19,7 @@
 
 import org.apache.doris.catalog.FunctionSignature;
 import org.apache.doris.nereids.trees.expressions.Expression;
-import org.apache.doris.nereids.trees.expressions.functions.PropagateNullable;
+import org.apache.doris.nereids.trees.expressions.functions.AlwaysNullable;
 import org.apache.doris.nereids.trees.expressions.shape.UnaryExpression;
 import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
 import org.apache.doris.nereids.types.JsonType;
@@ -34,7 +34,7 @@
  * explode_json_array_json_outer("[{"id":1,"name":"John"},{"id":2,"name":"Mary"},{"id":3,"name":"Bob"}]"),
  * generate 3 lines include '{"id":1,"name":"John"}', '{"id":2,"name":"Mary"}' and '{"id":3,"name":"Bob"}'.
  */
-public class ExplodeJsonArrayJsonOuter extends TableGeneratingFunction implements UnaryExpression, PropagateNullable {
+public class ExplodeJsonArrayJsonOuter extends TableGeneratingFunction implements UnaryExpression, AlwaysNullable {
     public static final List<FunctionSignature> SIGNATURES = ImmutableList.of(
             FunctionSignature.ret(JsonType.INSTANCE).args(JsonType.INSTANCE),
             FunctionSignature.ret(VarcharType.SYSTEM_DEFAULT).args(VarcharType.SYSTEM_DEFAULT)

regression-test/data/query_p0/sql_functions/table_function/explode_json_array.out

@@ -227,3 +227,8 @@
 400	Dan	50	4	Street 4	22.214	b
 400	Dan	50	4	Street 4	214.1	b
 
+-- !explode_json_array17 --
+4	{"a":1}
+4	{"b":2}
+4	{"c":3}
+

regression-test/suites/query_p0/sql_functions/table_function/explode_json_array.groovy

@@ -89,5 +89,32 @@ suite("explode_json_array") {
     qt_explode_json_array16 """ SELECT id, name, age, class, address, d, c FROM person
                         LATERAL VIEW EXPLODE_JSON_ARRAY_STRING('[null, "b", null]') t1 as c 
                         LATERAL VIEW EXPLODE_JSON_ARRAY_DOUBLE('[1.23, 22.214, 214.1]') t2 as d 
-                        ORDER BY id, c, d """        
+                        ORDER BY id, c, d """    
+    sql """ DROP TABLE IF EXISTS json_array_example """
+    sql """
+        CREATE TABLE json_array_example (
+            id INT,
+            json_array STRING
+        )DUPLICATE KEY(id)
+        DISTRIBUTED BY HASH(id) BUCKETS AUTO
+        PROPERTIES (
+        "replication_allocation" = "tag.location.default: 1");
+    """   
+    sql """ 
+                INSERT INTO json_array_example (id, json_array) VALUES
+            (1, '[1, 2, 3, 4, 5]'),
+            (2, '[1.1, 2.2, 3.3, 4.4]'),
+            (3, '["apple", "banana", "cherry"]'),
+            (4, '[{"a": 1}, {"b": 2}, {"c": 3}]'),
+            (5, '[]'),
+            (6, 'NULL');
+    """ 
+
+    qt_explode_json_array17 """ 
+        SELECT id, e1
+        FROM json_array_example
+        LATERAL VIEW EXPLODE_JSON_ARRAY_JSON_OUTER(json_array) tmp1 AS e1
+        WHERE id = 4 order by id, e1;
+    """ 
+
 }