diff --git a/dbms/src/Storages/MergeTree/MergeTreeIndices.h b/dbms/src/Storages/MergeTree/MergeTreeIndices.h
index 2ccba3195fe..738e0e3d3f7 100644
--- a/dbms/src/Storages/MergeTree/MergeTreeIndices.h
+++ b/dbms/src/Storages/MergeTree/MergeTreeIndices.h
@@ -31,9 +31,7 @@ struct MergeTreeIndexGranule
     virtual void serializeBinary(WriteBuffer & ostr) const = 0;
     virtual void deserializeBinary(ReadBuffer & istr) = 0;
 
-    virtual String toString() const = 0;
     virtual bool empty() const = 0;
-
     virtual void update(const Block & block, size_t * pos, size_t limit) = 0;
 };
 
diff --git a/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.cpp b/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.cpp
index d15e86a6e22..93b5a267dc0 100644
--- a/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.cpp
+++ b/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.cpp
@@ -52,20 +52,6 @@ void MergeTreeMinMaxGranule::deserializeBinary(ReadBuffer & istr)
     }
 }
 
-String MergeTreeMinMaxGranule::toString() const
-{
-    String res = "";
-
-    for (size_t i = 0; i < parallelogram.size(); ++i)
-    {
-        res += "["
-                + applyVisitor(FieldVisitorToString(), parallelogram[i].left) + ", "
-                + applyVisitor(FieldVisitorToString(), parallelogram[i].right) + "]";
-    }
-
-    return res;
-}
-
 void MergeTreeMinMaxGranule::update(const Block & block, size_t * pos, size_t limit)
 {
     size_t rows_read = std::min(limit, block.rows() - *pos);
diff --git a/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.h b/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.h
index ac1ca1787e1..1ba82098035 100644
--- a/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.h
+++ b/dbms/src/Storages/MergeTree/MergeTreeMinMaxIndex.h
@@ -20,9 +20,7 @@ struct MergeTreeMinMaxGranule : public MergeTreeIndexGranule
     void serializeBinary(WriteBuffer & ostr) const override;
     void deserializeBinary(ReadBuffer & istr) override;
 
-    String toString() const override;
     bool empty() const override { return parallelogram.empty(); }
-
     void update(const Block & block, size_t * pos, size_t limit) override;
 
     ~MergeTreeMinMaxGranule() override = default;
diff --git a/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.cpp b/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.cpp
index 857a55d11c5..d035d5281e9 100644
--- a/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.cpp
+++ b/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.cpp
@@ -80,29 +80,6 @@ void MergeTreeUniqueGranule::deserializeBinary(ReadBuffer & istr)
     set->insertFromBlock(block);
 }
 
-String MergeTreeUniqueGranule::toString() const
-{
-    String res;
-
-    const auto & columns = set->getSetElements();
-    for (size_t i = 0; i < index.columns.size(); ++i)
-    {
-        const auto & column = columns[i];
-        res += " [";
-        for (size_t j = 0; j < column->size(); ++j)
-        {
-            if (j != 0)
-                res += ", ";
-            Field field;
-            column->get(j, field);
-            res += applyVisitor(FieldVisitorToString(), field);
-        }
-        res += "]\n";
-    }
-
-    return res;
-}
-
 void MergeTreeUniqueGranule::update(const Block & new_block, size_t * pos, size_t limit)
 {
     size_t rows_read = std::min(limit, new_block.rows() - *pos);
diff --git a/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.h b/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.h
index d7ae892496a..cce5becf1ca 100644
--- a/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.h
+++ b/dbms/src/Storages/MergeTree/MergeTreeUniqueIndex.h
@@ -21,7 +21,6 @@ struct MergeTreeUniqueGranule : public MergeTreeIndexGranule
     void serializeBinary(WriteBuffer & ostr) const override;
     void deserializeBinary(ReadBuffer & istr) override;
 
-    String toString() const override;
     size_t size() const { return set->getTotalRowCount(); }
     bool empty() const override { return !size(); }