Fix CHAR data type in PostgreSQL mode

h2/src/main/org/h2/command/Command.java

@@ -18,6 +18,7 @@ import org.h2.message.DbException;
 import org.h2.message.Trace;
 import org.h2.result.ResultInterface;
 import org.h2.result.ResultWithGeneratedKeys;
+import org.h2.result.ResultWithPaddedStrings;
 import org.h2.util.MathUtils;
 
 /**
@@ -200,6 +201,9 @@ public abstract class Command implements CommandInterface {
                     try {
                         ResultInterface result = query(maxrows);
                         callStop = !result.isLazy();
+                        if (database.getMode().padFixedLengthStrings) {
+                            return ResultWithPaddedStrings.get(result);
+                        }
                         return result;
                     } catch (DbException e) {
                         start = filterConcurrentUpdate(e, start);

h2/src/main/org/h2/result/ResultWithPaddedStrings.java

+/*
+ * Copyright 2004-2019 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.result;
+
+import java.util.Arrays;
+import org.h2.engine.SessionInterface;
+import org.h2.util.MathUtils;
+import org.h2.value.TypeInfo;
+import org.h2.value.Value;
+import org.h2.value.ValueString;
+
+/**
+ * Result with padded fixed length strings.
+ */
+public class ResultWithPaddedStrings implements ResultInterface {
+
+    private final ResultInterface source;
+
+    /**
+     * Returns wrapped result if necessary, or original result if it does not
+     * contain visible CHAR columns.
+     *
+     * @param source
+     *            source result
+     * @return wrapped result or original result
+     */
+    public static ResultInterface get(ResultInterface source) {
+        int count = source.getVisibleColumnCount();
+        for (int i = 0; i < count; i++) {
+            if (source.getColumnType(i).getValueType() == Value.STRING_FIXED) {
+                return new ResultWithPaddedStrings(source);
+            }
+        }
+        return source;
+    }
+
+    /**
+     * Creates new instance of result.
+     *
+     * @param source
+     *            the source result
+     */
+    private ResultWithPaddedStrings(ResultInterface source) {
+        this.source = source;
+    }
+
+    @Override
+    public void reset() {
+        source.reset();
+    }
+
+    @Override
+    public Value[] currentRow() {
+        int count = source.getVisibleColumnCount();
+        Value[] row = Arrays.copyOf(source.currentRow(), count);
+        for (int i = 0; i < count; i++) {
+            TypeInfo type = source.getColumnType(i);
+            if (type.getValueType() == Value.STRING_FIXED) {
+                long precision = type.getPrecision();
+                if (precision == Integer.MAX_VALUE) {
+                    // CHAR is CHAR(1)
+                    precision = 1;
+                }
+                String s = row[i].getString();
+                if (s.length() < precision) {
+                    /*
+                     * Use ValueString to avoid truncation of spaces. There is
+                     * no difference between ValueStringFixed and ValueString
+                     * for JDBC layer anyway.
+                     */
+                    row[i] = ValueString.get(rightPadWithSpaces(s, MathUtils.convertLongToInt(precision)));
+                }
+            }
+        }
+        return row;
+    }
+
+    private static String rightPadWithSpaces(String s, int length) {
+        int used = s.length();
+        if (length <= used) {
+            return s;
+        }
+        char[] res = new char[length];
+        s.getChars(0, used, res, 0);
+        Arrays.fill(res, used, length, ' ');
+        return new String(res);
+    }
+
+    @Override
+    public boolean next() {
+        return source.next();
+    }
+
+    @Override
+    public int getRowId() {
+        return source.getRowId();
+    }
+
+    @Override
+    public boolean isAfterLast() {
+        return source.isAfterLast();
+    }
+
+    @Override
+    public int getVisibleColumnCount() {
+        return source.getVisibleColumnCount();
+    }
+
+    @Override
+    public int getRowCount() {
+        return source.getRowCount();
+    }
+
+    @Override
+    public boolean hasNext() {
+        return source.hasNext();
+    }
+
+    @Override
+    public boolean needToClose() {
+        return source.needToClose();
+    }
+
+    @Override
+    public void close() {
+        source.close();
+    }
+
+    @Override
+    public String getAlias(int i) {
+        return source.getAlias(i);
+    }
+
+    @Override
+    public String getSchemaName(int i) {
+        return source.getSchemaName(i);
+    }
+
+    @Override
+    public String getTableName(int i) {
+        return source.getTableName(i);
+    }
+
+    @Override
+    public String getColumnName(int i) {
+        return source.getColumnName(i);
+    }
+
+    @Override
+    public TypeInfo getColumnType(int i) {
+        return source.getColumnType(i);
+    }
+
+    @Override
+    public boolean isAutoIncrement(int i) {
+        return source.isAutoIncrement(i);
+    }
+
+    @Override
+    public int getNullable(int i) {
+        return source.getNullable(i);
+    }
+
+    @Override
+    public void setFetchSize(int fetchSize) {
+        source.setFetchSize(fetchSize);
+    }
+
+    @Override
+    public int getFetchSize() {
+        return source.getFetchSize();
+    }
+
+    @Override
+    public boolean isLazy() {
+        return source.isLazy();
+    }
+
+    @Override
+    public boolean isClosed() {
+        return source.isClosed();
+    }
+
+    @Override
+    public ResultInterface createShallowCopy(SessionInterface targetSession) {
+        ResultInterface copy = source.createShallowCopy(targetSession);
+        return copy != null ? new ResultWithPaddedStrings(copy) : null;
+    }
+
+}

h2/src/main/org/h2/value/Transfer.java

@@ -622,7 +622,7 @@ public class Transfer {
         case Value.STRING_IGNORECASE:
             return ValueStringIgnoreCase.get(readString());
         case Value.STRING_FIXED:
-            return ValueStringFixed.get(readString(), ValueStringFixed.PRECISION_DO_NOT_TRIM, null);
+            return ValueStringFixed.get(readString());
         case Value.BLOB: {
             long length = readLong();
             if (version >= Constants.TCP_PROTOCOL_VERSION_11) {

h2/src/main/org/h2/value/Value.java

@@ -788,7 +788,7 @@ public abstract class Value extends VersionedValue {
             case STRING_IGNORECASE:
                 return convertToStringIgnoreCase(mode);
             case STRING_FIXED:
-                return convertToStringFixed(precision, mode);
+                return convertToStringFixed(mode);
             case JAVA_OBJECT:
                 return convertToJavaObject();
             case ENUM:
@@ -1177,14 +1177,14 @@ public abstract class Value extends VersionedValue {
         return ValueStringIgnoreCase.get(s);
     }
 
-    private ValueString convertToStringFixed(int precision, Mode mode) {
+    private ValueString convertToStringFixed(Mode mode) {
         String s;
         if (getValueType() == BYTES && mode != null && mode.charToBinaryInUtf8) {
             s = new String(getBytesNoCopy(), StandardCharsets.UTF_8);
         } else {
             s = getString();
         }
-        return ValueStringFixed.get(s, precision, mode);
+        return ValueStringFixed.get(s);
     }
 
     private ValueJavaObject convertToJavaObject() {

h2/src/main/org/h2/value/ValueStringFixed.java

@@ -5,8 +5,6 @@
  */
 package org.h2.value;
 
-import java.util.Arrays;
-import org.h2.engine.Mode;
 import org.h2.engine.SysProperties;
 import org.h2.util.StringUtils;
 
@@ -15,18 +13,6 @@ import org.h2.util.StringUtils;
  */
 public class ValueStringFixed extends ValueString {
 
-    /**
-     * Special value for the precision in {@link #get(String, int, Mode)} to indicate that the value
-     * should <i>not</i> be trimmed.
-     */
-    public static final int PRECISION_DO_NOT_TRIM = Integer.MIN_VALUE;
-
-    /**
-     * Special value for the precision in {@link #get(String, int, Mode)} to indicate
-     * that the default behaviour should of trimming the value should apply.
-     */
-    public static final int PRECISION_TRIM = -1;
-
     private static final ValueStringFixed EMPTY = new ValueStringFixed("");
 
     protected ValueStringFixed(String value) {
@@ -36,6 +22,7 @@ public class ValueStringFixed extends ValueString {
     private static String trimRight(String s) {
         return trimRight(s, 0);
     }
+
     private static String trimRight(String s, int minLength) {
         int endIndex = s.length() - 1;
         int i = endIndex;
@@ -46,17 +33,6 @@ public class ValueStringFixed extends ValueString {
         return s;
     }
 
-    private static String rightPadWithSpaces(String s, int length) {
-        int used = s.length();
-        if (length <= used) {
-            return s;
-        }
-        char[] res = new char[length];
-        s.getChars(0, used, res, 0);
-        Arrays.fill(res, used, length, ' ');
-        return new String(res);
-    }
-
     @Override
     public int getValueType() {
         return STRING_FIXED;
@@ -70,45 +46,7 @@ public class ValueStringFixed extends ValueString {
      * @return the value
      */
     public static ValueStringFixed get(String s) {
-        // Use the special precision constant PRECISION_TRIM to indicate
-        // default H2 behaviour of trimming the value.
-        return get(s, PRECISION_TRIM, null);
-    }
-
-    /**
-     * Get or create a fixed length string value for the given string.
-     * <p>
-     * This method will use a {@link Mode}-specific conversion when <code>mode</code> is not
-     * <code>null</code>.
-     * Otherwise it will use the default H2 behaviour of trimming the given string if
-     * <code>precision</code> is not {@link #PRECISION_DO_NOT_TRIM}.
-     *
-     * @param s the string
-     * @param precision if the {@link Mode#padFixedLengthStrings} indicates that strings should
-     *        be padded, this defines the overall length of the (potentially padded) string.
-     *        If the special constant {@link #PRECISION_DO_NOT_TRIM} is used the value will
-     *        not be trimmed.
-     * @param mode the database mode
-     * @return the value
-     */
-    public static ValueStringFixed get(String s, int precision, Mode mode) {
-        // Should fixed strings be padded?
-        if (mode != null && mode.padFixedLengthStrings) {
-            if (precision == Integer.MAX_VALUE) {
-                // CHAR without a length specification is identical to CHAR(1)
-                precision = 1;
-            }
-            if (s.length() < precision) {
-                // We have to pad
-                s = rightPadWithSpaces(s, precision);
-            } else {
-                // We should trim, because inserting 'A   ' into a CHAR(1) is possible!
-                s = trimRight(s, precision);
-            }
-        } else if (precision != PRECISION_DO_NOT_TRIM) {
-            // Default behaviour of H2
-            s = trimRight(s);
-        }
+        s = trimRight(s);
         int length = s.length();
         if (length == 0) {
             return EMPTY;

h2/src/test/org/h2/test/scripts/datatypes/char.sql

@@ -17,3 +17,59 @@ SELECT COLUMN_NAME, DATA_TYPE, TYPE_NAME, COLUMN_TYPE FROM INFORMATION_SCHEMA.CO
 
 DROP TABLE TEST;
 > ok
+
+CREATE TABLE TEST(C CHAR(2));
+> ok
+
+INSERT INTO TEST VALUES 'aa', 'b';
+> update count: 2
+
+SELECT * FROM TEST WHERE C = 'b';
+>> b
+
+SELECT * FROM TEST WHERE C = 'b ';
+>> b
+
+SELECT * FROM TEST WHERE C = 'b  ';
+>> b
+
+SELECT C || 'x' V FROM TEST;
+> V
+> ---
+> aax
+> bx
+> rows: 2
+
+DROP TABLE TEST;
+> ok
+
+SET MODE PostgreSQL;
+> ok
+
+CREATE TABLE TEST(C CHAR(2));
+> ok
+
+INSERT INTO TEST VALUES 'aa', 'b';
+> update count: 2
+
+SELECT * FROM TEST WHERE C = 'b';
+>> b
+
+SELECT * FROM TEST WHERE C = 'b ';
+>> b
+
+SELECT * FROM TEST WHERE C = 'b  ';
+>> b
+
+SELECT C || 'x' V FROM TEST;
+> V
+> ---
+> aax
+> bx
+> rows: 2
+
+DROP TABLE TEST;
+> ok
+
+SET MODE Regular;
+> ok