diff --git a/asterixdb/asterix-algebra/src/main/java/org/apache/asterix/translator/LangExpressionToPlanTranslator.java b/asterixdb/asterix-algebra/src/main/java/org/apache/asterix/translator/LangExpressionToPlanTranslator.java
index 077b39b..d5c916f 100644
--- a/asterixdb/asterix-algebra/src/main/java/org/apache/asterix/translator/LangExpressionToPlanTranslator.java
+++ b/asterixdb/asterix-algebra/src/main/java/org/apache/asterix/translator/LangExpressionToPlanTranslator.java
@@ -1120,7 +1120,8 @@
             }
             if (!function.isExternal()) {
                 // all non-external UDFs should've been inlined by now
-                throw new CompilationException(ErrorCode.COMPILATION_ILLEGAL_STATE, sourceLoc, signature);
+                throw new CompilationException(ErrorCode.COMPILATION_ILLEGAL_STATE, sourceLoc,
+                        "UDF not inlined: " + signature);
             }
             IFunctionInfo finfo = ExternalFunctionCompilerUtil.getExternalFunctionInfo(metadataProvider, function);
             AbstractFunctionCallExpression f = new ScalarFunctionCallExpression(finfo, args);
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.01.ddl.sqlpp b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.01.ddl.sqlpp
new file mode 100644
index 0000000..d930fc9
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.01.ddl.sqlpp
@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+/*
+ * Description  : Test inlining of UDFs
+ */
+
+drop dataverse experiments if exists;
+create dataverse experiments;
+use experiments;
+
+create function fun1(...) {
+  args[0] + args[1]
+};
+
+create function fun2(...) {
+  args[0] - args[1]
+};
+
+CREATE TYPE openType AS {id: int};
+CREATE DATASET ds(openType) primary key id;
\ No newline at end of file
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.02.update.sqlpp b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.02.update.sqlpp
new file mode 100644
index 0000000..22cfcc1
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.02.update.sqlpp
@@ -0,0 +1,22 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+use experiments;
+
+UPSERT INTO ds {"id": 1, "a": 1, "b": 2, "c": [10,20,30,40], "d": [100,200,300,400]};
\ No newline at end of file
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.03.query.sqlpp b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.03.query.sqlpp
new file mode 100644
index 0000000..5ae85ea
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/user-defined-functions/inline-in-expr/inline-in-expr.03.query.sqlpp
@@ -0,0 +1,25 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+USE experiments;
+
+SELECT -fun1(ds.a, ds.b) AS x1,
+ds.c[fun1(ds.a, ds.b)] AS x2,
+ds.d[-fun2(ds.a, ds.b)] AS x3
+FROM ds;
\ No newline at end of file
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/results/user-defined-functions/inline-in-expr/inline-in-expr.03.adm b/asterixdb/asterix-app/src/test/resources/runtimets/results/user-defined-functions/inline-in-expr/inline-in-expr.03.adm
new file mode 100644
index 0000000..145a6e3
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/results/user-defined-functions/inline-in-expr/inline-in-expr.03.adm
@@ -0,0 +1 @@
+{ "x1": -3, "x2": 40, "x3": 200 }
\ No newline at end of file
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/sqlpp_queries.xml b/asterixdb/asterix-app/src/test/resources/runtimets/sqlpp_queries.xml
index 509d90b..6f614ef 100644
--- a/asterixdb/asterix-app/src/test/resources/runtimets/sqlpp_queries.xml
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/sqlpp_queries.xml
@@ -13192,6 +13192,11 @@
   </test-group>
   <test-group name="user-defined-functions">
     <test-case FilePath="user-defined-functions">
+      <compilation-unit name="inline-in-expr">
+        <output-dir compare="Text">inline-in-expr</output-dir>
+      </compilation-unit>
+    </test-case>
+    <test-case FilePath="user-defined-functions">
       <compilation-unit name="bad-function-ddl-1">
         <output-dir compare="Text">bad-function-ddl-1</output-dir>
         <expected-error replacers="cloud:Default.experiments|def:experiments">Cannot find dataset TweetMessages in dataverse {0} nor an alias with name TweetMessages</expected-error>
diff --git a/asterixdb/asterix-lang-common/src/main/java/org/apache/asterix/lang/common/visitor/AbstractInlineUdfsVisitor.java b/asterixdb/asterix-lang-common/src/main/java/org/apache/asterix/lang/common/visitor/AbstractInlineUdfsVisitor.java
index 3975425..629be84 100644
--- a/asterixdb/asterix-lang-common/src/main/java/org/apache/asterix/lang/common/visitor/AbstractInlineUdfsVisitor.java
+++ b/asterixdb/asterix-lang-common/src/main/java/org/apache/asterix/lang/common/visitor/AbstractInlineUdfsVisitor.java
@@ -153,7 +153,14 @@
     public Boolean visit(IndexAccessor fa, Void arg) throws CompilationException {
         Pair<Boolean, Expression> p = inlineUdfsAndViewsInExpr(fa.getExpr());
         fa.setExpr(p.second);
-        return p.first;
+        boolean inlined = p.first;
+        Expression indexExpr = fa.getIndexExpr();
+        if (indexExpr != null) {
+            Pair<Boolean, Expression> p2 = inlineUdfsAndViewsInExpr(indexExpr);
+            fa.setIndexExpr(p2.second);
+            inlined |= p2.first;
+        }
+        return inlined;
     }
 
     @Override
@@ -250,7 +257,9 @@
 
     @Override
     public Boolean visit(UnaryExpr u, Void arg) throws CompilationException {
-        return u.getExpr().accept(this, arg);
+        Pair<Boolean, Expression> p = inlineUdfsAndViewsInExpr(u.getExpr());
+        u.setExpr(p.second);
+        return p.first;
     }
 
     @Override
@@ -275,7 +284,7 @@
         if (returnExpression != null) {
             Pair<Boolean, Expression> rewrittenReturnExpr = inlineUdfsAndViewsInExpr(returnExpression);
             insert.setReturnExpression(rewrittenReturnExpr.second);
-            changed |= rewrittenReturnExpr.first;
+            changed = rewrittenReturnExpr.first;
         }
         Pair<Boolean, Expression> rewrittenBodyExpression = inlineUdfsAndViewsInExpr(insert.getBody());
         insert.setBody(rewrittenBodyExpression.second);
@@ -284,10 +293,10 @@
 
     @Override
     public Boolean visit(CopyToStatement stmtCopy, Void arg) throws CompilationException {
-        boolean changed = false;
+        boolean changed;
 
         Pair<Boolean, Expression> queryBody = inlineUdfsAndViewsInExpr(stmtCopy.getBody());
-        changed |= queryBody.first;
+        changed = queryBody.first;
         stmtCopy.setBody(queryBody.second);
 
         Pair<Boolean, List<Expression>> path = inlineUdfsInExprList(stmtCopy.getPathExpressions());