chore: excluding test function factories from production run. Added handling...

chore: excluding test function factories from production run. Added handling of unexpected exceptions. Fixed #367 (#392)

core/src/main/java/io/questdb/PropServerConfiguration.java

@@ -949,6 +949,11 @@ public class PropServerConfiguration implements ServerConfiguration {
             return indexValueBlockSize;
         }
 
+        @Override
+        public boolean enableTestFactories() {
+            return false;
+        }
+
         @Override
         public int getDoubleToStrCastScale() {
             return doubleToStrCastScale;

core/src/main/java/io/questdb/cairo/CairoConfiguration.java

@@ -161,4 +161,6 @@ public interface CairoConfiguration {
     int getGroupByPoolCapacity();
 
     int getGroupByMapCapacity();
+
+    boolean enableTestFactories();
 }

core/src/main/java/io/questdb/cairo/CairoError.java

@@ -24,7 +24,9 @@
 
 package io.questdb.cairo;
 
-public class CairoError extends Error {
+import io.questdb.std.FlyweightMessageContainer;
+
+public class CairoError extends Error implements FlyweightMessageContainer {
     public CairoError(Throwable cause) {
         super(cause);
     }
@@ -32,4 +34,9 @@ public class CairoError extends Error {
     public CairoError(String message) {
         super(message);
     }
+
+    @Override
+    public CharSequence getFlyweightMessage() {
+        return getMessage();
+    }
 }

core/src/main/java/io/questdb/cairo/CairoException.java

@@ -24,12 +24,13 @@
 
 package io.questdb.cairo;
 
+import io.questdb.std.FlyweightMessageContainer;
 import io.questdb.std.Sinkable;
 import io.questdb.std.ThreadLocal;
 import io.questdb.std.str.CharSink;
 import io.questdb.std.str.StringSink;
 
-public class CairoException extends RuntimeException implements Sinkable {
+public class CairoException extends RuntimeException implements Sinkable, FlyweightMessageContainer {
     private static final ThreadLocal<CairoException> tlException = new ThreadLocal<>(CairoException::new);
     protected final StringSink message = new StringSink();
     private int errno;
@@ -63,6 +64,7 @@ public class CairoException extends RuntimeException implements Sinkable {
         return this;
     }
 
+    @Override
     public CharSequence getFlyweightMessage() {
         return message;
     }

core/src/main/java/io/questdb/cairo/DefaultCairoConfiguration.java

@@ -52,6 +52,11 @@ public class DefaultCairoConfiguration implements CairoConfiguration {
         return 16;
     }
 
+    @Override
+    public boolean enableTestFactories() {
+        return true;
+    }
+
     @Override
     public int getCreateAsSelectRetryCount() {
         return 5;

core/src/main/java/io/questdb/cutlass/http/HttpConnectionContext.java

@@ -28,14 +28,7 @@ import io.questdb.cairo.CairoSecurityContext;
 import io.questdb.cairo.security.CairoSecurityContextImpl;
 import io.questdb.log.Log;
 import io.questdb.log.LogFactory;
-import io.questdb.network.IOContext;
-import io.questdb.network.IODispatcher;
-import io.questdb.network.IOOperation;
-import io.questdb.network.Net;
-import io.questdb.network.NetworkFacade;
-import io.questdb.network.PeerDisconnectedException;
-import io.questdb.network.PeerIsSlowToReadException;
-import io.questdb.network.ServerDisconnectException;
+import io.questdb.network.*;
 import io.questdb.std.Chars;
 import io.questdb.std.Mutable;
 import io.questdb.std.ObjectPool;
@@ -177,7 +170,7 @@ public class HttpConnectionContext implements IOContext, Locality, Mutable {
         return responseSink.getSimple();
     }
 
-    private void completeRequest(HttpRequestProcessor processor) throws PeerDisconnectedException, PeerIsSlowToReadException {
+    private void completeRequest(HttpRequestProcessor processor) throws PeerDisconnectedException, PeerIsSlowToReadException, ServerDisconnectException {
         LOG.debug().$("complete [fd=").$(fd).$(']').$();
         processor.onRequestComplete(this);
     }

core/src/main/java/io/questdb/cutlass/http/HttpException.java

@@ -24,12 +24,13 @@
 
 package io.questdb.cutlass.http;
 
+import io.questdb.std.FlyweightMessageContainer;
 import io.questdb.std.Sinkable;
 import io.questdb.std.ThreadLocal;
 import io.questdb.std.str.CharSink;
 import io.questdb.std.str.StringSink;
 
-public class HttpException extends RuntimeException implements Sinkable {
+public class HttpException extends RuntimeException implements Sinkable, FlyweightMessageContainer {
     private static final ThreadLocal<HttpException> tlException = new ThreadLocal<>(HttpException::new);
     private final StringSink message = new StringSink();
 
@@ -41,7 +42,7 @@ public class HttpException extends RuntimeException implements Sinkable {
     }
 
     public CharSequence getFlyweightMessage() {
-        return tlException.get().getFlyweightMessage();
+        return message;
     }
 
     @Override

core/src/main/java/io/questdb/cutlass/http/HttpRequestProcessor.java

@@ -31,7 +31,7 @@ import io.questdb.network.ServerDisconnectException;
 public interface HttpRequestProcessor {
     void onHeadersReady(HttpConnectionContext context);
 
-    void onRequestComplete(HttpConnectionContext context) throws PeerDisconnectedException, PeerIsSlowToReadException;
+    void onRequestComplete(HttpConnectionContext context) throws PeerDisconnectedException, PeerIsSlowToReadException, ServerDisconnectException;
 
     default void resumeRecv(HttpConnectionContext context) {
     }

core/src/main/java/io/questdb/cutlass/http/processors/JsonQueryProcessor.java

@@ -24,10 +24,6 @@
 
 package io.questdb.cutlass.http.processors;
 
-import java.io.Closeable;
-
-import org.jetbrains.annotations.Nullable;
-
 import io.questdb.MessageBus;
 import io.questdb.cairo.CairoEngine;
 import io.questdb.cairo.CairoError;
@@ -36,11 +32,7 @@ import io.questdb.cairo.sql.InsertMethod;
 import io.questdb.cairo.sql.InsertStatement;
 import io.questdb.cairo.sql.ReaderOutOfDateException;
 import io.questdb.cairo.sql.RecordCursorFactory;
-import io.questdb.cutlass.http.HttpChunkedResponseSocket;
-import io.questdb.cutlass.http.HttpConnectionContext;
-import io.questdb.cutlass.http.HttpRequestHeader;
-import io.questdb.cutlass.http.HttpRequestProcessor;
-import io.questdb.cutlass.http.LocalValue;
+import io.questdb.cutlass.http.*;
 import io.questdb.cutlass.text.Utf8Exception;
 import io.questdb.griffin.CompiledQuery;
 import io.questdb.griffin.SqlCompiler;
@@ -48,17 +40,12 @@ import io.questdb.griffin.SqlException;
 import io.questdb.griffin.SqlExecutionContextImpl;
 import io.questdb.log.Log;
 import io.questdb.log.LogFactory;
-import io.questdb.network.IOOperation;
-import io.questdb.network.NoSpaceLeftInResponseBufferException;
-import io.questdb.network.PeerDisconnectedException;
-import io.questdb.network.PeerIsSlowToReadException;
-import io.questdb.std.Chars;
-import io.questdb.std.Misc;
-import io.questdb.std.NanosecondClock;
-import io.questdb.std.Numbers;
-import io.questdb.std.NumericException;
-import io.questdb.std.ObjList;
+import io.questdb.network.*;
+import io.questdb.std.*;
 import io.questdb.std.str.DirectByteCharSequence;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.Closeable;
 
 public class JsonQueryProcessor implements HttpRequestProcessor, Closeable {
     private static final LocalValue<JsonQueryProcessorState> LV = new LocalValue<>();
@@ -102,7 +89,7 @@ public class JsonQueryProcessor implements HttpRequestProcessor, Closeable {
         Misc.free(compiler);
     }
 
-    public void execute0(JsonQueryProcessorState state) throws PeerDisconnectedException, PeerIsSlowToReadException {
+    public void execute0(JsonQueryProcessorState state) throws PeerDisconnectedException, PeerIsSlowToReadException, ServerDisconnectException {
         state.startExecutionTimer();
         final HttpConnectionContext context = state.getHttpConnectionContext();
         // do not set random for new request to avoid copying random from previous request into next one
@@ -129,9 +116,12 @@ public class JsonQueryProcessor implements HttpRequestProcessor, Closeable {
         } catch (SqlException e) {
             syntaxError(context.getChunkedResponseSocket(), e, state, configuration.getKeepAliveHeader());
             readyForNextRequest(context);
-        } catch (CairoException | CairoError e) {
-            internalError(context.getChunkedResponseSocket(), e, state);
+        } catch (CairoError | CairoException e) {
+            internalError(context.getChunkedResponseSocket(), e.getFlyweightMessage(), e, state);
             readyForNextRequest(context);
+        } catch (Throwable e) {
+            LOG.error().$("Uh-oh. Error!").$(e).$();
+            throw ServerDisconnectException.INSTANCE;
         }
     }
 
@@ -142,7 +132,7 @@ public class JsonQueryProcessor implements HttpRequestProcessor, Closeable {
     @Override
     public void onRequestComplete(
             HttpConnectionContext context
-    ) throws PeerDisconnectedException, PeerIsSlowToReadException {
+    ) throws PeerDisconnectedException, PeerIsSlowToReadException, ServerDisconnectException {
         JsonQueryProcessorState state = LV.get(context);
         if (state == null) {
             LV.set(context, state = new JsonQueryProcessorState(
@@ -360,11 +350,12 @@ public class JsonQueryProcessor implements HttpRequestProcessor, Closeable {
 
     private void internalError(
             HttpChunkedResponseSocket socket,
+            CharSequence message,
             Throwable e,
             JsonQueryProcessorState state
     ) throws PeerDisconnectedException, PeerIsSlowToReadException {
-        state.error().$("Server error executing query ").utf8(state.getQuery()).$(e).$();
-        sendException(socket, 0, e.getMessage(), 500, state.getQuery(), configuration.getKeepAliveHeader());
+        state.error().$("internal error [q=`").utf8(state.getQuery()).$("`, ex=").$(e).$();
+        sendException(socket, 0, message, 500, state.getQuery(), configuration.getKeepAliveHeader());
     }
 
     private boolean parseUrl(

core/src/main/java/io/questdb/cutlass/http/processors/TextImportProcessor.java

@@ -24,9 +24,7 @@
 
 package io.questdb.cutlass.http.processors;
 
-import io.questdb.cairo.CairoEngine;
-import io.questdb.cairo.ColumnType;
-import io.questdb.cairo.PartitionBy;
+import io.questdb.cairo.*;
 import io.questdb.cairo.sql.RecordMetadata;
 import io.questdb.cutlass.http.*;
 import io.questdb.cutlass.text.Atomicity;
@@ -35,10 +33,7 @@ import io.questdb.cutlass.text.TextLoader;
 import io.questdb.log.Log;
 import io.questdb.log.LogFactory;
 import io.questdb.network.*;
-import io.questdb.std.CharSequenceIntHashMap;
-import io.questdb.std.Chars;
-import io.questdb.std.LongList;
-import io.questdb.std.Misc;
+import io.questdb.std.*;
 import io.questdb.std.str.CharSink;
 
 import java.io.Closeable;
@@ -264,7 +259,7 @@ public class TextImportProcessor implements HttpRequestProcessor, HttpMultipartC
                     transientState.analysed = true;
                     transientState.textLoader.setState(TextLoader.LOAD_DATA);
                 }
-            } catch (TextException e) {
+            } catch (TextException | CairoException | CairoError e) {
                 handleTextException(e);
             }
         }
@@ -338,7 +333,7 @@ public class TextImportProcessor implements HttpRequestProcessor, HttpMultipartC
             if (transientState.messagePart == MESSAGE_DATA) {
                 sendResponse(transientContext);
             }
-        } catch (TextException e) {
+        } catch (TextException | CairoException | CairoError e) {
             handleTextException(e);
         }
     }
@@ -398,7 +393,7 @@ public class TextImportProcessor implements HttpRequestProcessor, HttpMultipartC
         state.clear();
     }
 
-    private void handleTextException(TextException e)
+    private void handleTextException(FlyweightMessageContainer e)
             throws PeerDisconnectedException, PeerIsSlowToReadException, ServerDisconnectException {
         sendError(transientContext, e.getFlyweightMessage(), Chars.equalsNc("json", transientContext.getRequestHeader().getUrlParam("fmt")));
         throw ServerDisconnectException.INSTANCE;

core/src/main/java/io/questdb/cutlass/json/JsonException.java

@@ -24,12 +24,13 @@
 
 package io.questdb.cutlass.json;
 
+import io.questdb.std.FlyweightMessageContainer;
 import io.questdb.std.Sinkable;
 import io.questdb.std.ThreadLocal;
 import io.questdb.std.str.CharSink;
 import io.questdb.std.str.StringSink;
 
-public class JsonException extends Exception implements Sinkable {
+public class JsonException extends Exception implements Sinkable, FlyweightMessageContainer {
     private static final ThreadLocal<JsonException> tlException = new ThreadLocal<>(JsonException::new);
     private final StringSink message = new StringSink();
     private int position;
@@ -45,6 +46,7 @@ public class JsonException extends Exception implements Sinkable {
         return ex;
     }
 
+    @Override
     public CharSequence getFlyweightMessage() {
         return message;
     }

core/src/main/java/io/questdb/cutlass/text/TextException.java

@@ -24,13 +24,14 @@
 
 package io.questdb.cutlass.text;
 
+import io.questdb.std.FlyweightMessageContainer;
 import io.questdb.std.Numbers;
 import io.questdb.std.Sinkable;
 import io.questdb.std.ThreadLocal;
 import io.questdb.std.str.CharSink;
 import io.questdb.std.str.StringSink;
 
-public class TextException extends Exception implements Sinkable {
+public class TextException extends Exception implements Sinkable, FlyweightMessageContainer {
     private static final ThreadLocal<TextException> tlException = new ThreadLocal<>(TextException::new);
     private final StringSink message = new StringSink();
 
@@ -42,6 +43,7 @@ public class TextException extends Exception implements Sinkable {
         return te;
     }
 
+    @Override
     public CharSequence getFlyweightMessage() {
         return message;
     }

core/src/main/java/io/questdb/griffin/FunctionParser.java

@@ -81,7 +81,7 @@ public class FunctionParser implements PostOrderTreeTraversalAlgo.Visitor {
 
     public FunctionParser(CairoConfiguration configuration, Iterable<FunctionFactory> functionFactories) {
         this.configuration = configuration;
-        loadFunctionFactories(functionFactories);
+        loadFunctionFactories(functionFactories, configuration.enableTestFactories());
     }
 
     public static int getArgType(char c) {
@@ -204,14 +204,14 @@ public class FunctionParser implements PostOrderTreeTraversalAlgo.Visitor {
         return ex;
     }
 
-    private static SqlException invalidArgument(CharSequence message, ExpressionNode node, ObjList<Function> args, CharSequence expected, int offset, int count) {
+    private static SqlException invalidArgument(ExpressionNode node, ObjList<Function> args, CharSequence expected, int offset, int count) {
         SqlException ex = SqlException.position(node.position);
-        ex.put(message);
+        ex.put("unexpected argument for function: ");
         ex.put(node.token);
         ex.put(". expected args: ");
         ex.put('(');
         if (expected != null) {
-            for (int i = 0, n = count; i < n; i++) {
+            for (int i = 0; i < count; i++) {
                 if (i > 0) {
                     ex.put(',');
                 }
@@ -670,9 +670,9 @@ public class FunctionParser implements PostOrderTreeTraversalAlgo.Visitor {
             if (candidateSignature != null) {
                 final int sigArgOffset = candidateSignature.indexOf('(') + 1;
                 int sigArgCount = candidateSignature.length() - 1 - sigArgOffset;
-                throw invalidArgument("unexpected argument for function: ", node, args, candidateSignature, sigArgOffset, sigArgCount);
+                throw invalidArgument(node, args, candidateSignature, sigArgOffset, sigArgCount);
             } else {
-                throw invalidArgument("unexpected argument for function: ", node, args, "", 0, 0);
+                throw invalidArgument(node, args, "", 0, 0);
             }
         }
 
@@ -815,41 +815,43 @@ public class FunctionParser implements PostOrderTreeTraversalAlgo.Visitor {
         addFactoryToList(extraList, name, factory);
     }
 
-    private void loadFunctionFactories(Iterable<FunctionFactory> functionFactories) {
+    private void loadFunctionFactories(Iterable<FunctionFactory> functionFactories, boolean enableTestFactories) {
+        LOG.info().$("loading functions [test=").$(enableTestFactories).$(']').$();
         for (FunctionFactory factory : functionFactories) {
+            if (!factory.getClass().getName().contains("test") || enableTestFactories) {
+                final String sig = factory.getSignature();
+                final int openBraceIndex;
+                try {
+                    openBraceIndex = validateSignatureAndGetNameSeparator(sig);
+                } catch (SqlException e) {
+                    LOG.error().$((Sinkable) e).$(" [signature=").$(factory.getSignature()).$(",class=").$(factory.getClass().getName()).$(']').$();
+                    continue;
+                }
 
-            final String sig = factory.getSignature();
-            final int openBraceIndex;
-            try {
-                openBraceIndex = validateSignatureAndGetNameSeparator(sig);
-            } catch (SqlException e) {
-                LOG.error().$((Sinkable) e).$(" [signature=").$(factory.getSignature()).$(",class=").$(factory.getClass().getName()).$(']').$();
-                continue;
-            }
-
-            final String name = sig.substring(0, openBraceIndex);
-            addFactoryToList(factories, name, factory);
-
-            // Add != counterparts to equality function factories
-            if (factory instanceof AbstractBooleanFunctionFactory) {
-                switch (name) {
-                    case "=":
-                        addFactory(booleanFactories, "!=", factory);
-                        break;
-                    case "<":
-                        // `a < b` == `a >= b`
-                        addFactory(booleanFactories, ">=", factory);
-                        if (sig.charAt(2) == sig.charAt(3)) {
-                            // `a < b` == `b > a`
-                            addFactory(commutativeBooleanFactories, ">", factory);
-                            // `a < b` == `b > a` == `b <= a`
-                            addFactory(booleanFactories, "<=", factory);
-                            addFactory(commutativeBooleanFactories, "<=", factory);
-                        }
-                        break;
+                final String name = sig.substring(0, openBraceIndex);
+                addFactoryToList(factories, name, factory);
+
+                // Add != counterparts to equality function factories
+                if (factory instanceof AbstractBooleanFunctionFactory) {
+                    switch (name) {
+                        case "=":
+                            addFactory(booleanFactories, "!=", factory);
+                            break;
+                        case "<":
+                            // `a < b` == `a >= b`
+                            addFactory(booleanFactories, ">=", factory);
+                            if (sig.charAt(2) == sig.charAt(3)) {
+                                // `a < b` == `b > a`
+                                addFactory(commutativeBooleanFactories, ">", factory);
+                                // `a < b` == `b > a` == `b <= a`
+                                addFactory(booleanFactories, "<=", factory);
+                                addFactory(commutativeBooleanFactories, "<=", factory);
+                            }
+                            break;
+                    }
+                } else if (factory.isGroupBy()) {
+                    groupByFunctionNames.add(name);
                 }
-            } else if (factory.isGroupBy()) {
-                groupByFunctionNames.add(name);
             }
         }
     }

core/src/main/java/io/questdb/griffin/SqlException.java

@@ -25,12 +25,13 @@
 package io.questdb.griffin;
 
 import io.questdb.cairo.ColumnType;
+import io.questdb.std.FlyweightMessageContainer;
 import io.questdb.std.Sinkable;
 import io.questdb.std.ThreadLocal;
 import io.questdb.std.str.CharSink;
 import io.questdb.std.str.StringSink;
 
-public class SqlException extends Exception implements Sinkable {
+public class SqlException extends Exception implements Sinkable, FlyweightMessageContainer {
     private static final ThreadLocal<SqlException> tlException = new ThreadLocal<>(SqlException::new);
     private final StringSink message = new StringSink();
     private int position;
@@ -75,6 +76,7 @@ public class SqlException extends Exception implements Sinkable {
                 .put(", to=").put(toName).put(']');
     }
 
+    @Override
     public CharSequence getFlyweightMessage() {
         return message;
     }

core/src/main/java/io/questdb/griffin/engine/functions/bind/BindException.java

@@ -24,12 +24,13 @@
 
 package io.questdb.griffin.engine.functions.bind;
 
+import io.questdb.std.FlyweightMessageContainer;
 import io.questdb.std.Sinkable;
 import io.questdb.std.ThreadLocal;
 import io.questdb.std.str.CharSink;
 import io.questdb.std.str.StringSink;
 
-public class BindException extends RuntimeException implements Sinkable {
+public class BindException extends RuntimeException implements Sinkable, FlyweightMessageContainer {
     private static final ThreadLocal<BindException> tlException = new ThreadLocal<>(BindException::new);
     private final StringSink message = new StringSink();
 
@@ -43,6 +44,7 @@ public class BindException extends RuntimeException implements Sinkable {
         return ex;
     }
 
+    @Override
     public CharSequence getFlyweightMessage() {
         return message;
     }

core/src/main/java/io/questdb/griffin/engine/functions/test/TestNPEFactory.java

+/*******************************************************************************
+ *     ___                  _   ____  ____
+ *    / _ \ _   _  ___  ___| |_|  _ \| __ )
+ *   | | | | | | |/ _ \/ __| __| | | |  _ \
+ *   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
+ *    \__\_\\__,_|\___||___/\__|____/|____/
+ *
+ *  Copyright (c) 2014-2019 Appsicle
+ *  Copyright (c) 2019-2020 QuestDB
+ *
+ *  Licensed 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.
+ *
+ ******************************************************************************/
+
+package io.questdb.griffin.engine.functions.test;
+
+import io.questdb.cairo.CairoConfiguration;
+import io.questdb.cairo.sql.Function;
+import io.questdb.cairo.sql.Record;
+import io.questdb.cairo.sql.SymbolTableSource;
+import io.questdb.griffin.FunctionFactory;
+import io.questdb.griffin.SqlException;
+import io.questdb.griffin.SqlExecutionContext;
+import io.questdb.griffin.engine.functions.BooleanFunction;
+import io.questdb.std.ObjList;
+
+public class TestNPEFactory implements FunctionFactory {
+    @Override
+    public String getSignature() {
+        return "npe()";
+    }
+
+    @Override
+    public Function newInstance(ObjList<Function> args, int position, CairoConfiguration configuration) throws SqlException {
+        return NPEFunction.INSTANCE;
+    }
+
+    private static class NPEFunction extends BooleanFunction {
+
+        private final static NPEFunction INSTANCE = new NPEFunction(0);
+
+        public NPEFunction(int position) {
+            super(position);
+        }
+
+        @Override
+        public boolean getBool(Record rec) {
+            throw new NullPointerException();
+        }
+
+        @Override
+        public void init(SymbolTableSource symbolTableSource, SqlExecutionContext executionContext) {
+
+        }
+    }
+}

core/src/main/java/io/questdb/griffin/engine/table/ShowColumnsRecordCursorFactory.java

@@ -39,8 +39,8 @@ public class ShowColumnsRecordCursorFactory implements RecordCursorFactory {
     private static final int N_TYPE_COL = 1;
     static {
         final GenericRecordMetadata metadata = new GenericRecordMetadata();
-        metadata.add(new TableColumnMetadata("columnName", ColumnType.STRING));
-        metadata.add(new TableColumnMetadata("columnType", ColumnType.STRING));
+        metadata.add(new TableColumnMetadata("column", ColumnType.STRING));
+        metadata.add(new TableColumnMetadata("type", ColumnType.STRING));
         METADATA = metadata;
     }
 

core/src/main/java/io/questdb/std/FlyweightMessageContainer.java

+/*******************************************************************************
+ *     ___                  _   ____  ____
+ *    / _ \ _   _  ___  ___| |_|  _ \| __ )
+ *   | | | | | | |/ _ \/ __| __| | | |  _ \
+ *   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
+ *    \__\_\\__,_|\___||___/\__|____/|____/
+ *
+ *  Copyright (c) 2014-2019 Appsicle
+ *  Copyright (c) 2019-2020 QuestDB
+ *
+ *  Licensed 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.
+ *
+ ******************************************************************************/
+
+package io.questdb.std;
+
+@FunctionalInterface
+public interface FlyweightMessageContainer {
+    CharSequence getFlyweightMessage();
+}

core/src/main/java/module-info.java

@@ -84,6 +84,7 @@ open module io.questdb {
             // test functions
             io.questdb.griffin.engine.functions.test.TestMatchFunctionFactory,
             TestSumXDoubleGroupByFunctionFactory,
+            io.questdb.griffin.engine.functions.test.TestNPEFactory,
             io.questdb.griffin.engine.functions.test.TestSumTDoubleGroupByFunctionFactory,
             io.questdb.griffin.engine.functions.test.TestSumStringGroupByFunctionFactory,
             io.questdb.griffin.engine.functions.bool.OrFunctionFactory,

core/src/test/java/io/questdb/griffin/ShowTablesTest.java

@@ -52,7 +52,7 @@ public class ShowTablesTest extends AbstractGriffinTest {
     public void testShowColumnsWithSimpleTable() throws Exception {
         assertMemoryLeak(() -> {
             compiler.compile("create table balances(cust_id int, ccy symbol, balance double)", sqlExecutionContext);
-            assertQuery("columnName\tcolumnType\ncust_id\tINT\nccy\tSYMBOL\nbalance\tDOUBLE\n", "show columns from balances", null, false, sqlExecutionContext, false);
+            assertQuery("column\ttype\ncust_id\tINT\nccy\tSYMBOL\nbalance\tDOUBLE\n", "show columns from balances", null, false, sqlExecutionContext, false);
         });
     }
 
@@ -107,7 +107,7 @@ public class ShowTablesTest extends AbstractGriffinTest {
     public void testShowColumnsWithFunction() throws Exception {
         assertMemoryLeak(() -> {
             compiler.compile("create table balances(cust_id int, ccy symbol, balance double)", sqlExecutionContext);
-            assertQuery("columnName\tcolumnType\ncust_id\tINT\nccy\tSYMBOL\nbalance\tDOUBLE\n", "select * from table_columns('balances')", null, false, sqlExecutionContext, false);
+            assertQuery("column\ttype\ncust_id\tINT\nccy\tSYMBOL\nbalance\tDOUBLE\n", "select * from table_columns('balances')", null, false, sqlExecutionContext, false);
         });
     }
 

core/src/test/resources/META-INF/services/io.questdb.griffin.FunctionFactory

@@ -70,10 +70,36 @@
 #
 ################################################################################
 
+################################################################################
+#     ___                  _   ____  ____
+#    / _ \ _   _  ___  ___| |_|  _ \| __ )
+#   | | | | | | |/ _ \/ __| __| | | |  _ \
+#   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
+#    \__\_\\__,_|\___||___/\__|____/|____/
+#
+#  Copyright (c) 2014-2019 Appsicle
+#  Copyright (c) 2019-2020 QuestDB
+#
+#  Licensed 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.
+#
+################################################################################
+
 io.questdb.griffin.engine.functions.test.TestMatchFunctionFactory
 io.questdb.griffin.engine.functions.test.TestSumXDoubleGroupByFunctionFactory
 io.questdb.griffin.engine.functions.test.TestSumTDoubleGroupByFunctionFactory
 io.questdb.griffin.engine.functions.test.TestSumStringGroupByFunctionFactory
+io.questdb.griffin.engine.functions.test.TestNPEFactory
+
 
 # logical operations
 io.questdb.griffin.engine.functions.bool.OrFunctionFactory