Fix LOBs in data change delta tables

h2database · Jan 15, 2022 · 9c88724 · 9c88724
1 parent ccaadc0
commit 9c88724
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Showing 5 changed files with 52 additions and 3 deletions.
diff --git a/h2/src/docsrc/html/changelog.html b/h2/src/docsrc/html/changelog.html
@@ -21,6 +21,10 @@ <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
 <ul>
+<li>Issue #3376: Data cannot be read after insert of clob data > MAX_LENGTH_INPLACE_LOB with data change delta table
+</li>
+<li>PR #3377: Add -webExternalNames setting and fix WebServer.getConnection()
+</li>
 <li>PR #3367: Use faster checks of dimension systems of geometries
 </li>
 <li>PR #3369: Added v2 changes in migration docs

diff --git a/h2/src/main/org/h2/command/Parser.java b/h2/src/main/org/h2/command/Parser.java
@@ -1989,6 +1989,10 @@ private Table readDataChangeDeltaTable(String resultOptionName, int backupIndex)
             throw getSyntaxError();
         }
         read(CLOSE_PAREN);
+        if (currentSelect != null) {
+            // Lobs aren't copied, so use it for more safety
+            currentSelect.setNeverLazy(true);
+        }
         return new DataChangeDeltaTable(getSchemaWithDefault(), session, statement, resultOption);
     }
 

diff --git a/h2/src/main/org/h2/result/LocalResult.java b/h2/src/main/org/h2/result/LocalResult.java
@@ -62,6 +62,7 @@ public static LocalResult forTable(SessionLocal session, Table table) {
     private int visibleColumnCount;
     private int resultColumnCount;
     private Expression[] expressions;
+    private boolean forDataChangeDeltaTable;
     private long rowId, rowCount;
     private ArrayList<Value[]> rows;
     private SortOrder sort;
@@ -140,6 +141,13 @@ public void setMaxMemoryRows(int maxValue) {
         this.maxMemoryRows = maxValue;
     }
 
+    /**
+     * Sets value collection mode for data change delta tables.
+     */
+    public void setForDataChangeDeltaTable() {
+        forDataChangeDeltaTable = true;
+    }
+
     /**
      * Create a shallow copy of the result set. The data and a temporary table
      * (if there is any) is not copied.
@@ -343,10 +351,14 @@ private void cloneLobs(Value[] values) {
         for (int i = 0; i < values.length; i++) {
             Value v = values[i];
             if (v instanceof ValueLob) {
-                ValueLob v2 = ((ValueLob) v).copyToResult();
-                if (v2 != v) {
+                if (forDataChangeDeltaTable) {
                     containsLobs = true;
-                    values[i] = session.addTemporaryLob(v2);
+                } else {
+                    ValueLob v2 = ((ValueLob) v).copyToResult();
+                    if (v2 != v) {
+                        containsLobs = true;
+                        values[i] = session.addTemporaryLob(v2);
+                    }
                 }
             }
         }

diff --git a/h2/src/main/org/h2/table/DataChangeDeltaTable.java b/h2/src/main/org/h2/table/DataChangeDeltaTable.java
@@ -116,6 +116,7 @@ public ResultInterface getResult(SessionLocal session) {
         statement.prepare();
         int columnCount = expressions.length;
         LocalResult result = new LocalResult(session, expressions, columnCount, columnCount);
+        result.setForDataChangeDeltaTable();
         statement.update(result, resultOption);
         return result;
     }

diff --git a/h2/src/test/org/h2/test/scripts/other/data-change-delta-table.sql b/h2/src/test/org/h2/test/scripts/other/data-change-delta-table.sql
@@ -387,3 +387,31 @@ SELECT * FROM NEW TABLE (MERGE INTO TEST_VIEW TEST USING
 
 DROP TABLE TEST CASCADE;
 > ok
+
+CREATE TABLE TEST(ID BIGINT, DATA CHARACTER LARGE OBJECT);
+> ok
+
+INSERT INTO TEST VALUES (1, REPEAT('A', 1000));
+> update count: 1
+
+SELECT ID FROM FINAL TABLE (INSERT INTO TEST VALUES (2, REPEAT('B', 1000)));
+>> 2
+
+SELECT ID, SUBSTRING(DATA FROM 1 FOR 2) FROM TEST;
+> ID SUBSTRING(DATA FROM 1 FOR 2)
+> -- ----------------------------
+> 1  AA
+> 2  BB
+> rows: 2
+
+@reconnect
+
+SELECT ID, SUBSTRING(DATA FROM 1 FOR 2) FROM TEST;
+> ID SUBSTRING(DATA FROM 1 FOR 2)
+> -- ----------------------------
+> 1  AA
+> 2  BB
+> rows: 2
+
+DROP TABLE TEST;
+> ok