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diff --git a/SQLiteStudio3/coreSQLiteStudio/common/readwritelocker.h b/SQLiteStudio3/coreSQLiteStudio/common/readwritelocker.h
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+++ b/SQLiteStudio3/coreSQLiteStudio/common/readwritelocker.h
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+#ifndef READWRITELOCKER_H
+#define READWRITELOCKER_H
+
+#include "coreSQLiteStudio_global.h"
+#include "dialect.h"
+
+class QReadLocker;
+class QWriteLocker;
+class QReadWriteLock;
+
+/**
+ * @brief The ReadWriteLocker class
+ *
+ * This class behaves pretty much like QReadLocker or QWriteLocker
+ * (it actually uses those internally), except it can be either
+ * of those and this is to be decided at the moment of creation.
+ * Therefore the locker can work as read or write locker depending
+ * on an external condition.
+ * There's also a possibility to not lock anything as a third
+ * choice of working mode, so this also can be decided
+ * at construction moment.
+ */
+class API_EXPORT ReadWriteLocker
+{
+    public:
+        enum Mode
+        {
+            READ,
+            WRITE,
+            NONE
+        };
+
+        ReadWriteLocker(QReadWriteLock* lock, Mode mode);
+        ReadWriteLocker(QReadWriteLock* lock, const QString& query, Dialect dialect, bool noLock);
+        virtual ~ReadWriteLocker();
+
+        /**
+         * @brief Provides required locking mode for given query.
+         * @param query Query to be executed.
+         * @return Locking mode: READ or WRITE.
+         *
+         * Given the query this method analyzes what is the query and provides information if the query
+         * will do some changes on the database, or not. Then it returns proper locking mode that should
+         * be used for this query execution.
+         *
+         * Query execution methods from this class check if lock mode of the query to be executed isn't
+         * in conflict with the lock being currently applied on the dbOperLock (if any is applied at the moment).
+         *
+         * This method works on a very simple rule. It assumes that queries: SELECT, ANALYZE, EXPLAIN,
+         * and PRAGMA - are read-only, while all other queries are read-write.
+         * In case of PRAGMA this is not entirely true, but it's not like using PRAGMA for changing
+         * some setting would cause database state inconsistency. At least not from perspective of SQLiteStudio.
+         *
+         * In case of WITH statement it filters out the "WITH clause" and then checks for SELECT keyword.
+         */
+        static ReadWriteLocker::Mode getMode(const QString& query, Dialect dialect, bool noLock);
+
+    private:
+        void init(QReadWriteLock* lock, Mode mode);
+
+        QReadLocker* readLocker = nullptr;
+        QWriteLocker* writeLocker = nullptr;
+};
+
+#endif // READWRITELOCKER_H