SELECT ... FROM CSVREAD no longer creates a temporary file.

h2/src/main/org/h2/engine/FunctionAlias.java

@@ -470,5 +470,4 @@ public class FunctionAlias extends SchemaObjectBase {
         }
     }
 
-
 }

h2/src/main/org/h2/expression/Function.java

@@ -303,8 +303,8 @@ public class Function extends Expression implements FunctionCall {
         addFunctionNotDeterministic("NEXTVAL", NEXTVAL, VAR_ARGS, Value.LONG);
         addFunctionNotDeterministic("CURRVAL", CURRVAL, VAR_ARGS, Value.LONG);
         addFunction("ARRAY_GET", ARRAY_GET, 2, Value.STRING);
-        addFunction("CSVREAD", CSVREAD, VAR_ARGS, Value.RESULT_SET, false, false);
-        addFunction("CSVWRITE", CSVWRITE, VAR_ARGS, Value.INT, false, false);
+        addFunction("CSVREAD", CSVREAD, VAR_ARGS, Value.RESULT_SET, false, false, true);
+        addFunction("CSVWRITE", CSVWRITE, VAR_ARGS, Value.INT, false, false, false);
         addFunctionNotDeterministic("MEMORY_FREE", MEMORY_FREE, 0, Value.INT);
         addFunctionNotDeterministic("MEMORY_USED", MEMORY_USED, 0, Value.INT);
         addFunctionNotDeterministic("LOCK_MODE", LOCK_MODE, 0, Value.INT);
@@ -315,8 +315,8 @@ public class Function extends Expression implements FunctionCall {
         addFunctionWithNull("LEAST", LEAST, VAR_ARGS, Value.NULL);
         addFunctionWithNull("GREATEST", GREATEST, VAR_ARGS, Value.NULL);
         addFunction("CANCEL_SESSION", CANCEL_SESSION, 1, Value.BOOLEAN);
-        addFunction("SET", SET, 2, Value.NULL, false, false);
-        addFunction("FILE_READ", FILE_READ, VAR_ARGS, Value.NULL, false, true);
+        addFunction("SET", SET, 2, Value.NULL, false, false, false);
+        addFunction("FILE_READ", FILE_READ, VAR_ARGS, Value.NULL, false, true, false);
         addFunctionNotDeterministic("TRANSACTION_ID", TRANSACTION_ID, 0, Value.STRING);
 
         // TableFunction
@@ -335,7 +335,7 @@ public class Function extends Expression implements FunctionCall {
     }
 
     private static void addFunction(String name, int type, int parameterCount, int dataType,
-            boolean nullIfParameterIsNull, boolean deterministic) {
+            boolean nullIfParameterIsNull, boolean deterministic, boolean fast) {
         FunctionInfo info = new FunctionInfo();
         info.name = name;
         info.type = type;
@@ -343,19 +343,20 @@ public class Function extends Expression implements FunctionCall {
         info.dataType = dataType;
         info.nullIfParameterIsNull = nullIfParameterIsNull;
         info.deterministic = deterministic;
+        info.fast = fast;
         FUNCTIONS.put(name, info);
     }
 
     private static void addFunctionNotDeterministic(String name, int type, int parameterCount, int dataType) {
-        addFunction(name, type, parameterCount, dataType, true, false);
+        addFunction(name, type, parameterCount, dataType, true, false, false);
     }
 
     private static void addFunction(String name, int type, int parameterCount, int dataType) {
-        addFunction(name, type, parameterCount, dataType, true, true);
+        addFunction(name, type, parameterCount, dataType, true, true, false);
     }
 
     private static void addFunctionWithNull(String name, int type, int parameterCount, int dataType) {
-        addFunction(name, type, parameterCount, dataType, false, true);
+        addFunction(name, type, parameterCount, dataType, false, true, false);
     }
 
     /**
@@ -1224,7 +1225,7 @@ public class Function extends Expression implements FunctionCall {
     private static int getDatePart(String part) {
         Integer p = DATE_PART.get(StringUtils.toUpperEnglish(part));
         if (p == null) {
-            throw DbException.get(ErrorCode.INVALID_VALUE_2, "date part", part);
+            throw DbException.getInvalidValueException("date part", part);
         }
         return p.intValue();
     }
@@ -1986,4 +1987,8 @@ public class Function extends Expression implements FunctionCall {
         return info.deterministic;
     }
 
+    public boolean isFast() {
+        return info.fast;
+    }
+
 }

h2/src/main/org/h2/expression/FunctionCall.java

@@ -82,4 +82,12 @@ public interface FunctionCall {
      * @return true if it does
      */
     boolean isDeterministic();
+
+    /**
+     * Whether the function is fast, meaning the result shouldn't be cached.
+     *
+     * @return true if it is
+     */
+    boolean isFast();
+
 }

h2/src/main/org/h2/expression/FunctionInfo.java

@@ -40,4 +40,10 @@ class FunctionInfo {
      * If this function always returns the same value for the same parameters.
      */
     boolean deterministic;
+
+    /**
+     * Whether the function is fast, meaning the result shouldn't be cached.
+     */
+    boolean fast;
+
 }

h2/src/main/org/h2/expression/JavaFunction.java

@@ -164,4 +164,9 @@ public class JavaFunction extends Expression implements FunctionCall {
         }
         return super.getExpressionColumns(session);
     }
+
+    public boolean isFast() {
+        return false;
+    }
+
 }

h2/src/main/org/h2/index/FunctionCursor.java

@@ -13,11 +13,11 @@ import org.h2.result.SearchRow;
 import org.h2.value.Value;
 
 /**
- * A cursor for a function that returns a result set.
+ * A cursor for a function that returns a result.
  */
 public class FunctionCursor implements Cursor {
 
-    private ResultInterface result;
+    private final ResultInterface result;
     private Value[] values;
     private Row row;
 
@@ -41,7 +41,7 @@ public class FunctionCursor implements Cursor {
 
     public boolean next() {
         row = null;
-        if (result.next()) {
+        if (result != null && result.next()) {
             values = result.currentRow();
         } else {
             values = null;

h2/src/main/org/h2/index/FunctionCursorResultSet.java

+/*
+ * Copyright 2004-2010 H2 Group. Multiple-Licensed under the H2 License,
+ * Version 1.0, and under the Eclipse Public License, Version 1.0
+ * (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.index;
+
+import java.sql.ResultSet;
+import java.sql.ResultSetMetaData;
+import java.sql.SQLException;
+import org.h2.engine.Session;
+import org.h2.message.DbException;
+import org.h2.result.Row;
+import org.h2.result.SearchRow;
+import org.h2.value.DataType;
+import org.h2.value.Value;
+
+/**
+ * A cursor for a function that returns a JDBC result set.
+ */
+public class FunctionCursorResultSet implements Cursor {
+
+    private final Session session;
+    private final ResultSet result;
+    private final ResultSetMetaData meta;
+    private Value[] values;
+    private Row row;
+
+    FunctionCursorResultSet(Session session, ResultSet result) {
+        this.session = session;
+        this.result = result;
+        try {
+            this.meta = result.getMetaData();
+        } catch (SQLException e) {
+            throw DbException.convert(e);
+        }
+    }
+
+    public Row get() {
+        if (values == null) {
+            return null;
+        }
+        if (row == null) {
+            row = new Row(values, 1);
+        }
+        return row;
+    }
+
+    public SearchRow getSearchRow() {
+        return get();
+    }
+
+    public boolean next() {
+        row = null;
+        try {
+            if (result != null && result.next()) {
+                int columnCount = meta.getColumnCount();
+                values = new Value[columnCount];
+                for (int i = 0; i < columnCount; i++) {
+                    int type = DataType.convertSQLTypeToValueType(meta.getColumnType(i + 1));
+                    values[i] = DataType.readValue(session, result, i+1, type);
+                }
+            } else {
+                values = null;
+            }
+        } catch (SQLException e) {
+            throw DbException.convert(e);
+        }
+        return values != null;
+    }
+
+    public boolean previous() {
+        throw DbException.throwInternalError();
+    }
+
+}
\ No newline at end of file

h2/src/main/org/h2/index/FunctionIndex.java

@@ -8,7 +8,6 @@ package org.h2.index;
 
 import org.h2.engine.Session;
 import org.h2.message.DbException;
-import org.h2.result.ResultInterface;
 import org.h2.result.Row;
 import org.h2.result.SearchRow;
 import org.h2.table.FunctionTable;
@@ -20,8 +19,7 @@ import org.h2.table.IndexColumn;
  */
 public class FunctionIndex extends BaseIndex {
 
-    private FunctionTable functionTable;
-    private ResultInterface result;
+    private final FunctionTable functionTable;
 
     public FunctionIndex(FunctionTable functionTable, IndexColumn[] columns) {
         initBaseIndex(functionTable, 0, null, columns, IndexType.createNonUnique(true));
@@ -41,10 +39,11 @@ public class FunctionIndex extends BaseIndex {
     }
 
     public Cursor find(Session session, SearchRow first, SearchRow last) {
-        // TODO sometimes result.reset() would be enough (but not when
-        // parameters are used)
-        result = functionTable.getResult(session);
-        return new FunctionCursor(result);
+        if (functionTable.isFast()) {
+            return new FunctionCursorResultSet(session, functionTable.getResultSet(session));
+        } else {
+            return new FunctionCursor(functionTable.getResult(session));
+        }
     }
 
     public double getCost(Session session, int[] masks) {

h2/src/main/org/h2/table/FunctionTable.java

@@ -20,6 +20,7 @@ import org.h2.index.Index;
 import org.h2.index.IndexType;
 import org.h2.message.DbException;
 import org.h2.result.LocalResult;
+import org.h2.result.ResultInterface;
 import org.h2.result.Row;
 import org.h2.schema.Schema;
 import org.h2.value.DataType;
@@ -152,24 +153,21 @@ public class FunctionTable extends Table {
     }
 
     /**
-     * Read the result set from the function.
+     * Read the result from the function. This method caches the result.
      *
      * @param session the session
-     * @return the result set
+     * @return the result
      */
-    public LocalResult getResult(Session session) {
-        functionExpr = functionExpr.optimize(session);
-        Value v = functionExpr.getValue(session);
+    public ResultInterface getResult(Session session) {
+        ValueResultSet v = getValueResultSet(session);
+        if (v == null) {
+            return null;
+        }
         if (cachedResult != null && cachedValue == v) {
             cachedResult.reset();
             return cachedResult;
         }
-        if (v == ValueNull.INSTANCE) {
-            return new LocalResult();
-        }
-        ValueResultSet value = (ValueResultSet) v;
-        ResultSet rs = value.getResultSet();
-        LocalResult result = LocalResult.read(session,  rs, 0);
+        LocalResult result = LocalResult.read(session,  v.getResultSet(), 0);
         if (function.isDeterministic()) {
             cachedResult = result;
             cachedValue = v;
@@ -177,6 +175,30 @@ public class FunctionTable extends Table {
         return result;
     }
 
+    /**
+     * Read the result set from the function. This method doesn't cache.
+     *
+     * @param session the session
+     * @return the result set
+     */
+    public ResultSet getResultSet(Session session) {
+        ValueResultSet v = getValueResultSet(session);
+        return v == null ? null : v.getResultSet();
+    }
+
+    private ValueResultSet getValueResultSet(Session session) {
+        functionExpr = functionExpr.optimize(session);
+        Value v = functionExpr.getValue(session);
+        if (v == ValueNull.INSTANCE) {
+            return null;
+        }
+        return (ValueResultSet) v;
+    }
+
+    public boolean isFast() {
+        return function.isFast();
+    }
+
     public long getMaxDataModificationId() {
         // TODO optimization: table-as-a-function currently doesn't know the
         // last modified date