SQLite support only one statement at a time

SQLite driver support only one statement at a time. This fix makes the
exec and prepare call failed if more than one statements are given.
This is bug fix for QTBUG-21884. Also the behaviour is documented in
the API specification.

Task-number: QTBUG-21884
Change-Id: If1e25a0dd9f9ee38961ef478fc7909f6b05e360a
Reviewed-by: Yunqiao Yin <charles.yin@nokia.com>

2 files changed, 15 insertions, 2 deletions

diff --git a/src/sql/drivers/sqlite/qsql_sqlite.cpp b/src/sql/drivers/sqlite/qsql_sqlite.cpp
index 9fba6d6fe4..8294a55633 100644
--- a/src/sql/drivers/sqlite/qsql_sqlite.cpp
+++ b/src/sql/drivers/sqlite/qsql_sqlite.cpp
@@ -322,12 +322,14 @@ bool QSQLiteResult::prepare(const QString &query)
 
     setSelect(false);
 
+    const void *pzTail = NULL;
+
 #if (SQLITE_VERSION_NUMBER >= 3003011)
     int res = sqlite3_prepare16_v2(d->access, query.constData(), (query.size() + 1) * sizeof(QChar),
-                                   &d->stmt, 0);
+                                   &d->stmt, &pzTail);
 #else
     int res = sqlite3_prepare16(d->access, query.constData(), (query.size() + 1) * sizeof(QChar),
-                                &d->stmt, 0);
+                                &d->stmt, &pzTail);
 #endif
 
     if (res != SQLITE_OK) {
@@ -335,6 +337,11 @@ bool QSQLiteResult::prepare(const QString &query)
                      "Unable to execute statement"), QSqlError::StatementError, res));
         d->finalize();
         return false;
+    } else if (pzTail && !QString(reinterpret_cast<const QChar *>(pzTail)).trimmed().isEmpty()) {
+        setLastError(qMakeError(d->access, QCoreApplication::translate("QSQLiteResult",
+            "Unable to execute multiple statements at a time"), QSqlError::StatementError, SQLITE_MISUSE));
+        d->finalize();
+        return false;
     }
     return true;
 }
diff --git a/src/sql/kernel/qsqlquery.cpp b/src/sql/kernel/qsqlquery.cpp
index 4eb46f1790..fda6301bc0 100644
--- a/src/sql/kernel/qsqlquery.cpp
+++ b/src/sql/kernel/qsqlquery.cpp
@@ -338,6 +338,9 @@ bool QSqlQuery::isNull(int field) const
   Note that the last error for this query is reset when exec() is
   called.
 
+  For SQLite, the query string can contain only one statement at a time.
+  If more than one statements is give, the function returns false.
+
   Example:
 
   \snippet doc/src/snippets/sqldatabase/sqldatabase.cpp 34
@@ -887,6 +890,9 @@ void QSqlQuery::clear()
   syntactically wrong query succeeds, but every consecutive exec()
   will fail.
 
+  For SQLite, the query string can contain only one statement at a time.
+  If more than one statements are give, the function returns false.
+
   Example:
 
   \snippet doc/src/snippets/sqldatabase/sqldatabase.cpp 9