sqlite: Allow for duplicated placeholders with just one placeholder

This accounts for a case of a placeholder being duplicated in the
prepare query, but where only one placeholder was used. This amends
e4e87a2ece1e0c9901514fea094f31863b64b570

Task-number: QTBUG-68299
Change-Id: Ia92ee912facd51a13e7222886debb219b24442b0
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

2 files changed, 12 insertions, 2 deletions

diff --git a/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp b/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp
index a862e8d2a7..2a770d0245 100644
--- a/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp
+++ b/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp
@@ -496,10 +496,10 @@ bool QSQLiteResult::exec()
 
 #if (SQLITE_VERSION_NUMBER >= 3003011)
     // In the case of the reuse of a named placeholder
-    // We need to check explicitly that paramCount is greater than 1, as sqlite
+    // We need to check explicitly that paramCount is greater than or equal to 1, as sqlite
     // can end up in a case where for virtual tables it returns 0 even though it
     // has parameters
-    if (paramCount > 1 && paramCount < values.count()) {
+    if (paramCount >= 1 && paramCount < values.count()) {
         const auto countIndexes = [](int counter, const QVector<int> &indexList) {
                                       return counter + indexList.length();
                                   };
diff --git a/tests/auto/sql/kernel/qsqlquery/tst_qsqlquery.cpp b/tests/auto/sql/kernel/qsqlquery/tst_qsqlquery.cpp
index 23c8460133..38da5431fa 100644
--- a/tests/auto/sql/kernel/qsqlquery/tst_qsqlquery.cpp
+++ b/tests/auto/sql/kernel/qsqlquery/tst_qsqlquery.cpp
@@ -2347,6 +2347,16 @@ void tst_QSqlQuery::prepare_bind_exec()
         QCOMPARE(q.value(0).toInt(), 107);
         QCOMPARE(q.value(1).toString(), QString("name"));
         QCOMPARE(q.value(2).toString(), QString("107"));
+
+        // Test just duplicated placeholders
+        QVERIFY(q.prepare("insert into " + qtest_prepare + " (id, name, name2) values (110, :name, :name)"));
+        q.bindValue(":name", "name");
+        QVERIFY_SQL(q, exec());
+        QVERIFY(q.exec("select * from " + qtest_prepare + " where id > 109 order by id"));
+        QVERIFY(q.next());
+        QCOMPARE(q.value(0).toInt(), 110);
+        QCOMPARE(q.value(1).toString(), QString("name"));
+        QCOMPARE(q.value(2).toString(), QString("name"));
     } // end of SQLite scope
 }