Merge pull request #3869 from katzyn/information_schema

Fix INFORMATION_SCHEMA.SESSIONS.ISOLATION_LEVEL
h2database · Aug 15, 2023 · 6a51ba4 · 6a51ba4
2 parents fcc5461 + 5083086
commit 6a51ba4
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Showing 4 changed files with 57 additions and 2 deletions.
diff --git a/h2/src/docsrc/html/changelog.html b/h2/src/docsrc/html/changelog.html
@@ -21,6 +21,8 @@ <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
 <ul>
+<li>Issue #3868: INFORMATION_SCHEMA.SESSIONS.ISOLATION_LEVEL returns isolation level of the current session in all rows
+</li>
 <li>RP #3865: Add possibility to enable virtual worker threads in TCP, Web, and PG servers on Java 21+
 </li>
 <li>PR #3864: Improve performance of TCP client driver when it is used from virtual threads

diff --git a/h2/src/main/org/h2/table/InformationSchemaTable.java b/h2/src/main/org/h2/table/InformationSchemaTable.java
@@ -2866,7 +2866,7 @@ private void sessions(SessionLocal session, ArrayList<Row> rows, SessionLocal s)
                 // SESSION_START
                 s.getSessionStart(),
                 // ISOLATION_LEVEL
-                session.getIsolationLevel().getSQL(),
+                s.getIsolationLevel().getSQL(),
                 // EXECUTING_STATEMENT
                 command == null ? null : command.toString(),
                 // EXECUTING_STATEMENT_START

diff --git a/h2/src/main/org/h2/table/InformationSchemaTableLegacy.java b/h2/src/main/org/h2/table/InformationSchemaTableLegacy.java
@@ -1891,7 +1891,7 @@ public ArrayList<Row> generateRows(SessionLocal session, SearchRow first, Search
                             // SESSION_START
                             s.getSessionStart(),
                             // ISOLATION_LEVEL
-                            session.getIsolationLevel().getSQL(),
+                            s.getIsolationLevel().getSQL(),
                             // STATEMENT
                             command == null ? null : command.toString(),
                             // STATEMENT_START

diff --git a/h2/src/test/org/h2/test/db/TestTransaction.java b/h2/src/test/org/h2/test/db/TestTransaction.java
@@ -61,6 +61,7 @@ public void test() throws Exception {
         testIsolationLevels4();
         testIsolationLevelsCountAggregate();
         testIsolationLevelsCountAggregate2();
+        testIsolationLevelsMetadata();
         deleteDb("transaction");
     }
 
@@ -1308,4 +1309,56 @@ private void testIsolationLevelCountAggregate2(PreparedStatement prep, long expe
         assertEquals(expected, rs.getLong(1));
     }
 
+    private void testIsolationLevelsMetadata() throws SQLException {
+        deleteDb("transaction");
+        try (Connection conn1 = getConnection("transaction"); Connection conn2 = getConnection("transaction")) {
+            PreparedStatement prep1 = conn1.prepareStatement(
+                    "SELECT ISOLATION_LEVEL, SESSION_ID = SESSION_ID() FROM INFORMATION_SCHEMA.SESSIONS");
+            PreparedStatement prep2 = conn2.prepareStatement(
+                    "SELECT ISOLATION_LEVEL, SESSION_ID = SESSION_ID() FROM INFORMATION_SCHEMA.SESSIONS");
+            for (int isolationLevel : new int[] { Connection.TRANSACTION_READ_UNCOMMITTED,
+                    Connection.TRANSACTION_READ_COMMITTED, Connection.TRANSACTION_REPEATABLE_READ,
+                    Constants.TRANSACTION_SNAPSHOT, Connection.TRANSACTION_SERIALIZABLE }) {
+                conn2.setTransactionIsolation(isolationLevel);
+                String level;
+                switch (isolationLevel) {
+                case Connection.TRANSACTION_READ_UNCOMMITTED:
+                    level = "READ UNCOMMITTED";
+                    break;
+                case Connection.TRANSACTION_READ_COMMITTED:
+                    level = "READ COMMITTED";
+                    break;
+                case Connection.TRANSACTION_REPEATABLE_READ:
+                    level = "REPEATABLE READ";
+                    break;
+                case Constants.TRANSACTION_SNAPSHOT:
+                    level = "SNAPSHOT";
+                    break;
+                case Connection.TRANSACTION_SERIALIZABLE:
+                    level = "SERIALIZABLE";
+                    break;
+                default:
+                    throw new IllegalArgumentException();
+                }
+                ResultSet rs = prep1.executeQuery();
+                while (rs.next()) {
+                    if (rs.getBoolean(2)) {
+                        assertEquals("READ COMMITTED", rs.getString(1));
+                    } else {
+                        assertEquals(level, rs.getString(1));
+                    }
+                }
+                rs = prep2.executeQuery();
+                while (rs.next()) {
+                    if (rs.getBoolean(2)) {
+                        assertEquals(level, rs.getString(1));
+                    } else {
+                        assertEquals("READ COMMITTED", rs.getString(1));
+                    }
+                }
+            }
+        }
+        deleteDb("transaction");
+    }
+
 }