SQLite: enable support for named placeholders

SQLite has been supporting named placeholders for some time now and the
code of the module is also written in that sense. The only thing that
currently fails is the parameter count check. If the named placeholder
is used several times then the parameter count will not match the
value count. This patch adds a second check in that case. This use
case is already tested by tst_qsqlquery.

[ChangeLog][QtSql][SQLite] Named placeholder can now be used.
If compiling Qt by hand and using system libraries, this feature
requires at least SQLite 3.3.11.

Change-Id: I1f6fa93f72bd809136894eafce0a2ae5cf6a62db
Reviewed-by: Jesus Fernandez <Jesus.Fernandez@qt.io>
Reviewed-by: Andy Shaw <andy.shaw@qt.io>

1 files changed, 27 insertions, 2 deletions

diff --git a/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp b/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp
index 8f336fd173..dd773fb022 100644
--- a/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp
+++ b/src/plugins/sqldrivers/sqlite/qsql_sqlite.cpp
@@ -432,8 +432,27 @@ bool QSQLiteResult::exec()
         d->finalize();
         return false;
     }
+
     int paramCount = sqlite3_bind_parameter_count(d->stmt);
-    if (paramCount == values.count()) {
+    bool paramCountIsValid = paramCount == values.count();
+
+#if (SQLITE_VERSION_NUMBER >= 3003011)
+    // In the case of the reuse of a named placeholder
+    if (!paramCountIsValid) {
+        const auto countIndexes = [](int counter, const QList<int>& indexList) {
+                                      return counter + indexList.length();
+                                  };
+
+        const int bindParamCount = std::accumulate(d->indexes.cbegin(),
+                                                   d->indexes.cend(),
+                                                   0,
+                                                   countIndexes);
+
+        paramCountIsValid = bindParamCount == values.count();
+    }
+#endif
+
+    if (paramCountIsValid) {
         for (int i = 0; i < paramCount; ++i) {
             res = SQLITE_OK;
             const QVariant value = values.at(i);
@@ -629,11 +648,17 @@ bool QSQLiteDriver::hasFeature(DriverFeature f) const
     case EventNotifications:
         return true;
     case QuerySize:
-    case NamedPlaceholders:
     case BatchOperations:
     case MultipleResultSets:
     case CancelQuery:
         return false;
+    case NamedPlaceholders:
+#if (SQLITE_VERSION_NUMBER < 3003011)
+        return false;
+#else
+        return true;
+#endif
+
     }
     return false;
 }