Merge pull request #1551 from katzyn/for_update

Add support for SELECT FOR UPDATE with JOINs in MVStore mode

h2/src/docsrc/help/help.csv

@@ -39,10 +39,10 @@ Multiple set operators (UNION, INTERSECT, MINUS, EXCEPT) are evaluated
 from left to right. For compatibility with other databases and future versions
 of H2 please use parentheses.
 
-If FOR UPDATE is specified, the tables are locked for writing. When using
-MVCC, only the selected rows are locked as in an UPDATE statement.
-In this case, aggregate, GROUP BY, DISTINCT queries or joins
-are not allowed in this case.
+If FOR UPDATE is specified, the tables or rows are locked for writing.
+This clause is not allowed in DISTINCT queries and in queries with non-window aggregates, GROUP BY, or HAVING clauses.
+When using default MVStore engine only the selected rows are locked as in an UPDATE statement.
+With PageStore engine the whole tables are locked.
 ","
 SELECT * FROM TEST;
 SELECT * FROM TEST ORDER BY NAME;

h2/src/docsrc/html/changelog.html

@@ -21,6 +21,14 @@ Change Log
 
 <h2>Next Version (unreleased)</h2>
 <ul>
+<li>Issue #1549: [RFE] Implement locking modes (select for update)
+</li>
+<li>PR #1548: Add AsynchronousFileChannel-based experimental FilePathAsync
+</li>
+<li>PR #1547: Speedup unused chunks collection
+</li>
+<li>PR #1546: Tiny optimization: use `System.arraycopy` when possible
+</li>
 <li>PR #1545: Export datetime value functions to SQL using standard syntax
 </li>
 <li>Issue #1371: NPE in CacheLRU

h2/src/docsrc/textbase/_messages_en.prop

@@ -175,6 +175,7 @@
 90142=Step size must not be zero
 90143=Row {1} not found in primary index {0}
 90144=Authenticator not enabled on database {0}
+90145=FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=General error: {0}
 HY004=Unknown data type: {0}
 HYC00=Feature not supported: {0}

h2/src/main/org/h2/api/ErrorCode.java

@@ -2030,8 +2030,20 @@ public class ErrorCode {
      */
     public static final int AUTHENTICATOR_NOT_AVAILABLE = 90144;
 
+    /**
+     * The error with code <code>90145</code> is thrown when trying to execute a
+     * SELECT statement with non-window aggregates, DISTINCT, GROUP BY, or
+     * HAVING clauses together with FOR UPDATE clause.
+     *
+     * <pre>
+     * SELECT DISTINCT NAME FOR UPDATE;
+     * SELECT MAX(VALUE) FOR UPDATE;
+     * </pre>
+     */
+    public static final int FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT = 90145;
+
 
-    // next is 90145
+    // next is 90146
 
     private ErrorCode() {
         // utility class

h2/src/main/org/h2/command/dml/Select.java

@@ -442,10 +442,12 @@ public class Select extends Query {
         int rowNumber = 0;
         setCurrentRowNumber(0);
         int sampleSize = getSampleSizeValue(session);
+        ArrayList<Row>[] forUpdateRows = initForUpdateRows();
         while (topTableFilter.next()) {
             setCurrentRowNumber(rowNumber + 1);
             if (isConditionMet()) {
                 rowNumber++;
+                addForUpdateRow(forUpdateRows);
                 groupData.nextSource();
                 updateAgg(columnCount, stage);
                 if (sampleSize > 0 && rowNumber >= sampleSize) {
@@ -453,6 +455,7 @@ public class Select extends Query {
                 }
             }
         }
+        lockForUpdateRows(forUpdateRows);
         groupData.done();
     }
 
@@ -627,7 +630,7 @@ public class Select extends Query {
                 limitRows = Long.MAX_VALUE;
             }
         }
-        ArrayList<Row> forUpdateRows = this.isForUpdateMvcc ? Utils.<Row>newSmallArrayList() : null;
+        ArrayList<Row>[] forUpdateRows = initForUpdateRows();
         int sampleSize = getSampleSizeValue(session);
         LazyResultQueryFlat lazyResult = new LazyResultQueryFlat(expressionArray,
                 sampleSize, columnCount);
@@ -640,9 +643,7 @@ public class Select extends Query {
         }
         Value[] row = null;
         while (result.getRowCount() < limitRows && lazyResult.next()) {
-            if (forUpdateRows != null) {
-                topTableFilter.lockRowAdd(forUpdateRows);
-            }
+            addForUpdateRow(forUpdateRows);
             row = lazyResult.currentRow();
             result.addRow(row);
         }
@@ -653,18 +654,45 @@ public class Select extends Query {
                 if (sort.compare(expected, row) != 0) {
                     break;
                 }
-                if (forUpdateRows != null) {
-                    topTableFilter.lockRowAdd(forUpdateRows);
-                }
+                addForUpdateRow(forUpdateRows);
                 result.addRow(row);
             }
             result.limitsWereApplied();
         }
-        if (forUpdateRows != null) {
-            topTableFilter.lockRows(forUpdateRows);
+        lockForUpdateRows(forUpdateRows);
+        return null;
     }
+
+    private ArrayList<Row>[] initForUpdateRows() {
+        if (!this.isForUpdateMvcc) {
             return null;
         }
+        int count = filters.size();
+        @SuppressWarnings("unchecked")
+        ArrayList<Row>[] rows = new ArrayList[count];
+        for (int i = 0; i < count; i++) {
+            rows[i] = Utils.<Row>newSmallArrayList();
+        }
+        return rows;
+    }
+
+    private void addForUpdateRow(ArrayList<Row>[] forUpdateRows) {
+        if (forUpdateRows != null) {
+            int count = filters.size();
+            for (int i = 0; i < count; i++) {
+                filters.get(i).lockRowAdd(forUpdateRows[i]);
+            }
+        }
+    }
+
+    private void lockForUpdateRows(ArrayList<Row>[] forUpdateRows) {
+        if (forUpdateRows != null) {
+            int count = filters.size();
+            for (int i = 0; i < count; i++) {
+                filters.get(i).lockRows(forUpdateRows[i]);
+            }
+        }
+    }
 
     private static void skipOffset(LazyResultSelect lazyResult, long offset, boolean quickOffset) {
         if (quickOffset) {
@@ -763,21 +791,6 @@ public class Select extends Query {
         topTableFilter.startQuery(session);
         topTableFilter.reset();
         boolean exclusive = isForUpdate && !isForUpdateMvcc;
-        if (isForUpdateMvcc) {
-            if (isGroupQuery) {
-                throw DbException.getUnsupportedException(
-                        "MVCC=TRUE && FOR UPDATE && GROUP");
-            } else if (isAnyDistinct()) {
-                throw DbException.getUnsupportedException(
-                        "MVCC=TRUE && FOR UPDATE && DISTINCT");
-            } else if (isQuickAggregateQuery) {
-                throw DbException.getUnsupportedException(
-                        "MVCC=TRUE && FOR UPDATE && AGGREGATE");
-            } else if (topTableFilter.getJoin() != null) {
-                throw DbException.getUnsupportedException(
-                        "MVCC=TRUE && FOR UPDATE && JOIN");
-            }
-        }
         topTableFilter.lock(session, exclusive, exclusive);
         ResultTarget to = result != null ? result : target;
         lazy &= to == null;
@@ -1451,9 +1464,11 @@ public class Select extends Query {
 
     @Override
     public void setForUpdate(boolean b) {
+        if (b && (isAnyDistinct() || isGroupQuery)) {
+            throw DbException.get(ErrorCode.FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT);
+        }
         this.isForUpdate = b;
-        if (session.getDatabase().getSettings().selectForUpdateMvcc &&
-                session.getDatabase().isMVStore()) {
+        if (session.getDatabase().isMVStore()) {
             isForUpdateMvcc = b;
         }
     }

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

@@ -296,14 +296,6 @@ public class DbSettings extends SettingsBase {
      */
     public final boolean rowId = get("ROWID", true);
 
-    /**
-     * Database setting <code>SELECT_FOR_UPDATE_MVCC</code>
-     * (default: true).<br />
-     * If set, SELECT .. FOR UPDATE queries lock only the selected rows when
-     * using MVCC.
-     */
-    public final boolean selectForUpdateMvcc = get("SELECT_FOR_UPDATE_MVCC", true);
-
     /**
      * Database setting <code>SHARE_LINKED_CONNECTIONS</code>
      * (default: true).<br />

h2/src/main/org/h2/message/DbException.java

@@ -566,6 +566,7 @@ public class DbException extends RuntimeException {
         case CAN_ONLY_ASSIGN_TO_VARIABLE_1:
         case PUBLIC_STATIC_JAVA_METHOD_NOT_FOUND_1:
         case JAVA_OBJECT_SERIALIZER_CHANGE_WITH_DATA_TABLE:
+        case FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT:
             return new JdbcSQLSyntaxErrorException(message, sql, state, errorCode, cause, stackTrace);
         case HEX_STRING_ODD_1:
         case HEX_STRING_WRONG_1:

h2/src/main/org/h2/mvstore/MVStore.java

@@ -1419,7 +1419,8 @@ public class MVStore {
                 Set<Long> inspectedRoots = new HashSet<>();
                 do {
                     inspectVersion(rootReference, collector, executorService, executingThreadCounter, inspectedRoots);
-                } while (rootReference.version >= oldestVersionToKeep && (rootReference = rootReference.previous) != null);
+                } while (rootReference.version >= oldestVersionToKeep
+                        && (rootReference = rootReference.previous) != null);
             }
             return collector.getReferenced();
         } finally {

h2/src/main/org/h2/res/_messages_cs.prop

@@ -175,6 +175,7 @@
 90142=#Step size must not be zero
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=Obecná chyba: {0}
 HY004=Neznámý datový typ: {0}
 HYC00=Vlastnost není podporována: {0}

h2/src/main/org/h2/res/_messages_de.prop

@@ -175,6 +175,7 @@
 90142=Schrittgrösse darf nicht 0 sein
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=Allgemeiner Fehler: {0}
 HY004=Unbekannter Datentyp: {0}
 HYC00=Dieses Feature wird nicht unterstützt: {0}

h2/src/main/org/h2/res/_messages_en.prop

@@ -175,6 +175,7 @@
 90142=Step size must not be zero
 90143=Row {1} not found in primary index {0}
 90144=Authenticator not enabled on database {0}
+90145=FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=General error: {0}
 HY004=Unknown data type: {0}
 HYC00=Feature not supported: {0}

h2/src/main/org/h2/res/_messages_es.prop

@@ -175,6 +175,7 @@
 90142=#Step size must not be zero
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=Error General : {0}
 HY004=Tipo de dato desconocido : {0}
 HYC00=Caracteristica no soportada: {0}

h2/src/main/org/h2/res/_messages_fr.prop

@@ -175,6 +175,7 @@
 90142=La taille de l''étape ne doit pas être de 0
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=Erreur générale: {0}
 HY004=Type de données inconnu: {0}
 HYC00=Fonctionnalité non supportée: {0}

h2/src/main/org/h2/res/_messages_ja.prop

@@ -175,6 +175,7 @@
 90142=ステップサイズに0は指定できません
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=一般エラー: {0}
 HY004=不明なデータ型: {0}
 HYC00=機能はサポートされていません: {0}

h2/src/main/org/h2/res/_messages_pl.prop

@@ -175,6 +175,7 @@
 90142=#Step size must not be zero
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=Błąd ogólny: {0}
 HY004=Nieznany typ danych: {0}
 HYC00=Cecha nie jest wspierana: {0}

h2/src/main/org/h2/res/_messages_pt_br.prop

@@ -175,6 +175,7 @@
 90142=#Step size must not be zero
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=Erro geral: {0}
 HY004=Tipo de dados desconhecido: {0}
 HYC00=Recurso não suportado: {0}

h2/src/main/org/h2/res/_messages_ru.prop

@@ -175,6 +175,7 @@
 90142=Размер шага не должен быть равен нулю
 90143=Строка {1} не найдена в первичном индексе {0}
 90144=Внешняя аутентификация не включена в базе данных {0}
+90145=FOR UPDATE не допускается в запросе с DISTINCT или запросе с группировкой
 HY000=Внутренняя ошибка: {0}
 HY004=Неизвестный тип данных: {0}
 HYC00=Данная функция не поддерживается: {0}

h2/src/main/org/h2/res/_messages_sk.prop

@@ -175,6 +175,7 @@
 90142=#Step size must not be zero
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=Všeobecná chyba: {0}
 HY004=Neznámy dátový typ: {0}
 HYC00=Vlastnosť nie je podporovaná: {0}

h2/src/main/org/h2/res/_messages_zh_cn.prop

@@ -175,6 +175,7 @@
 90142=#Step size must not be zero
 90143=#Row {1} not found in primary index {0}
 90144=#Authenticator not enabled on database {0}
+90145=#FOR UPDATE is not allowed in DISTINCT or grouped select
 HY000=常规错误: {0}
 HY004=位置数据类型: {0}
 HYC00=不支持的特性: {0}

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

@@ -280,7 +280,7 @@ public class TestCases extends TestDb {
         stat.execute("create table test(id int primary key)");
         assertThrows(ErrorCode.COLUMN_IS_REFERENCED_1, stat).
                 execute("alter table test alter column id " +
-                        "set default ifnull((select max(id) from test for update)+1, 0)");
+                        "set default ifnull((select max(id) from test)+1, 0)");
         stat.execute("drop table test");
         conn.close();
     }

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

@@ -158,17 +158,38 @@ public class TestTransaction extends TestDb {
         conn.setAutoCommit(false);
         Statement stat = conn.createStatement();
         stat.execute("create table test(id int primary key, name varchar)");
+        stat.execute("create table test2(id int primary key, name varchar)");
         stat.execute("insert into test values(1, 'Hello'), (2, 'World')");
+        stat.execute("insert into test2 values(1, 'A'), (2, 'B')");
         conn.commit();
-        PreparedStatement prep = conn.prepareStatement(
-                "select * from test for update");
+        testConcurrentSelectForUpdateImpl(conn, "*");
+        testConcurrentSelectForUpdateImpl(conn, "*, count(*) over ()");
+        conn.close();
+    }
+
+    private void testConcurrentSelectForUpdateImpl(Connection conn, String expressions) throws SQLException {
+        Connection conn2;
+        PreparedStatement prep;
+        prep = conn.prepareStatement("select * from test for update");
         prep.execute();
-        Connection conn2 = getConnection("transaction");
+        conn2 = getConnection("transaction");
+        conn2.setAutoCommit(false);
+        assertThrows(ErrorCode.LOCK_TIMEOUT_1, conn2.createStatement()).
+                execute("select " + expressions + " from test for update");
+        conn2.close();
+        conn.commit();
+
+        prep = conn.prepareStatement("select " + expressions
+                + " from test join test2 on test.id = test2.id for update");
+        prep.execute();
+        conn2 = getConnection("transaction");
         conn2.setAutoCommit(false);
         assertThrows(ErrorCode.LOCK_TIMEOUT_1, conn2.createStatement()).
                 execute("select * from test for update");
+        assertThrows(ErrorCode.LOCK_TIMEOUT_1, conn2.createStatement()).
+                execute("select * from test2 for update");
         conn2.close();
-        conn.close();
+        conn.commit();
     }
 
     private void testForUpdate() throws SQLException {

h2/src/test/org/h2/test/mvcc/TestMvcc2.java

@@ -126,22 +126,14 @@ public class TestMvcc2 extends TestDb {
     }
 
     private void testSelectForUpdate() throws SQLException {
-        Connection conn = getConnection("mvcc2;SELECT_FOR_UPDATE_MVCC=true");
-        Connection conn2 = getConnection("mvcc2;SELECT_FOR_UPDATE_MVCC=true");
+        Connection conn = getConnection("mvcc2");
+        Connection conn2 = getConnection("mvcc2");
         Statement stat = conn.createStatement();
         stat.execute("create table test(id int primary key, name varchar)");
         conn.setAutoCommit(false);
         stat.execute("insert into test select x, 'Hello' from system_range(1, 10)");
         stat.execute("select * from test where id = 3 for update");
         conn.commit();
-        assertThrows(ErrorCode.FEATURE_NOT_SUPPORTED_1, stat).
-                execute("select sum(id) from test for update");
-        assertThrows(ErrorCode.FEATURE_NOT_SUPPORTED_1, stat).
-                execute("select distinct id from test for update");
-        assertThrows(ErrorCode.FEATURE_NOT_SUPPORTED_1, stat).
-                execute("select id from test group by id for update");
-        assertThrows(ErrorCode.FEATURE_NOT_SUPPORTED_1, stat).
-                execute("select t1.id from test t1, test t2 for update");
         stat.execute("select * from test where id = 3 for update");
         conn2.setAutoCommit(false);
         conn2.createStatement().execute("select * from test where id = 4 for update");

h2/src/test/org/h2/test/scripts/dml/select.sql

@@ -407,3 +407,35 @@ SELECT * EXCEPT (T1.A, T2.D) FROM TEST1 T1, TEST2 T2;
 
 DROP TABLE TEST1, TEST2;
 > ok
+
+CREATE TABLE TEST(ID INT PRIMARY KEY, VALUE INT NOT NULL);
+> ok
+
+INSERT INTO TEST VALUES (1, 1), (2, 1), (3, 2);
+> update count: 3
+
+SELECT ID, VALUE FROM TEST FOR UPDATE;
+> ID VALUE
+> -- -----
+> 1  1
+> 2  1
+> 3  2
+> rows: 3
+
+SELECT DISTINCT VALUE FROM TEST FOR UPDATE;
+> exception FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT
+
+SELECT DISTINCT ON(VALUE) ID, VALUE FROM TEST FOR UPDATE;
+> exception FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT
+
+SELECT SUM(VALUE) FROM TEST FOR UPDATE;
+> exception FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT
+
+SELECT ID FROM TEST GROUP BY VALUE FOR UPDATE;
+> exception FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT
+
+SELECT 1 FROM TEST HAVING TRUE FOR UPDATE;
+> exception FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT
+
+DROP TABLE TEST;
+> ok

h2/src/tools/org/h2/build/doc/dictionary.txt

@@ -801,4 +801,4 @@ partitioned tri partitions
 
 discard enhancements nolock surefire logarithm
 qualification opportunity jumping exploited unacceptable vrs duplicated
-queryparser tokenized freeze factorings recompilation unenclosed
+queryparser tokenized freeze factorings recompilation unenclosed rfe dsync