CSVREAD: when reading the column names from the CSV file, column names that…

CSVREAD: when reading the column names from the CSV file, column names that contain no special characters are considered case insensitive now.

h2/src/docsrc/help/help.csv

@@ -3168,10 +3168,12 @@ Returns the result set of reading the CSV (comma separated values) file.
 For each parameter, NULL means the default value should be used.
 
 If the column names are specified (a list of column names separated with the
-fieldSeparator), those are used they are read from the file, otherwise
-(or if they are set to NULL) the first line of the file is interpreted as the column names.
-Column names are case sensitive, that means you need to use quoted identifiers
-unless the column names are capitalized (see below).
+fieldSeparator), those are used, otherwise (or if they are set to NULL) the first line of 
+the file is interpreted as the column names.
+In that case, column names that contain no special characters (only letters, '_',
+and digits; similar to the rule for Java identifiers) are considered case insensitive.
+Other column names are case sensitive, that means you need to use quoted identifiers
+(see below).
 
 The default charset is the default value for this system, and the default field separator
 is a comma. Missing unquoted values as well as data that matches nullString is

h2/src/main/org/h2/tools/Csv.java

@@ -159,9 +159,16 @@ public class Csv implements SimpleRowSource {
      * Reads from the CSV file and returns a result set. The rows in the result
      * set are created on demand, that means the file is kept open until all
      * rows are read or the result set is closed.
+     * <br />
+     * If the columns are read from the CSV file, then the following rules are
+     * used: columns names that start with a letter or '_', and only
+     * contain letters, '_', and digits, are considered case insensitive
+     * and are converted to uppercase. Other column names are considered
+     * case sensitive (that means they need to be quoted when accessed).
      *
      * @param inputFileName the file name
-     * @param colNames or null if the column names should be read from the CSV file
+     * @param colNames or null if the column names should be read from the CSV
+     *            file
      * @param charset the charset or null to use UTF-8
      * @return the result set
      * @throws SQLException
@@ -313,9 +320,15 @@ public class Csv implements SimpleRowSource {
                         break;
                     }
                 } else {
-                    list.add("COLUMN" + list.size());
+                    v = "COLUMN" + list.size();
+                    list.add(v);
                 }
             } else {
+                if (v.length() == 0) {
+                    v = "COLUMN" + list.size();
+                } else if (isSimpleColumnName(v)) {
+                    v = v.toUpperCase();
+                }
                 list.add(v);
                 if (endOfLine) {
                     break;
@@ -326,6 +339,25 @@ public class Csv implements SimpleRowSource {
         list.toArray(columnNames);
     }
 
+    private boolean isSimpleColumnName(String columnName) {
+        for (int i = 0; i < columnName.length(); i++) {
+            char ch = columnName.charAt(i);
+            if (i == 0) {
+                if (ch != '_' && !Character.isLetter(ch)) {
+                    return false;
+                }
+            } else {
+                if (ch != '_' && !Character.isLetterOrDigit(ch)) {
+                    return false;
+                }
+            }
+        }
+        if (columnName.length() == 0) {
+            return false;
+        }
+        return true;
+    }
+
     private void pushBack() {
         inputBufferPos--;
     }

h2/src/test/org/h2/test/db/TestCsv.java

@@ -8,6 +8,7 @@ package org.h2.test.db;
 
 import java.io.File;
 import java.io.InputStreamReader;
+import java.io.StringReader;
 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
@@ -16,7 +17,6 @@ import java.sql.SQLException;
 import java.sql.Statement;
 import java.util.ArrayList;
 import java.util.Random;
-
 import org.h2.store.fs.FileObject;
 import org.h2.store.fs.FileSystem;
 import org.h2.test.TestBase;
@@ -45,6 +45,7 @@ public class TestCsv extends TestBase {
     }
 
     public void test() throws Exception {
+        testColumnNames();
         testSpaceSeparated();
         testNull();
         testRandomData();
@@ -57,6 +58,15 @@ public class TestCsv extends TestBase {
         deleteDb("csv");
     }
 
+    private void testColumnNames() throws Exception {
+        ResultSet rs;
+        rs = Csv.getInstance().read(new StringReader("Id,First Name,2x,_x2\n1,2,3"), null);
+        assertEquals("ID", rs.getMetaData().getColumnName(1));
+        assertEquals("First Name", rs.getMetaData().getColumnName(2));
+        assertEquals("2x", rs.getMetaData().getColumnName(3));
+        assertEquals("_X2", rs.getMetaData().getColumnName(4));
+    }
+
     private void testSpaceSeparated() throws SQLException {
         deleteDb("csv");
         File f = new File(baseDir + "/testSpace.csv");
@@ -278,10 +288,10 @@ public class TestCsv extends TestBase {
         ResultSet rs = Csv.getInstance().read(fileName, null, "UTF8");
         ResultSetMetaData meta = rs.getMetaData();
         assertEquals(4, meta.getColumnCount());
-        assertEquals("a", meta.getColumnLabel(1));
-        assertEquals("b", meta.getColumnLabel(2));
-        assertEquals("c", meta.getColumnLabel(3));
-        assertEquals("d", meta.getColumnLabel(4));
+        assertEquals("A", meta.getColumnLabel(1));
+        assertEquals("B", meta.getColumnLabel(2));
+        assertEquals("C", meta.getColumnLabel(3));
+        assertEquals("D", meta.getColumnLabel(4));
         assertTrue(rs.next());
         assertEquals("201", rs.getString(1));
         assertEquals("-2", rs.getString(2));