impl

docs/en/sql-reference/functions/other-functions.md

@@ -1024,6 +1024,7 @@ The result of the function depends on the affected data blocks and the order of
 
 :::note
 Only returns neighbor inside the currently processed data block.
+Because of this error-prone behavior the function is DEPRECATED.
 :::
 
 The order of rows during calculation of `neighbor()` can differ from the order of rows returned to the user.
@@ -1134,6 +1135,7 @@ Returns 0 for the first row, and for subsequent rows the difference to the previ
 
 :::note
 Only returns differences inside the currently processed data block.
+Because of this error-prone behavior the function is DEPRECATED.
 :::
 
 The result of the function depends on the affected data blocks and the order of data in the block.
@@ -1207,6 +1209,10 @@ WHERE diff != 1
 
 ## runningDifferenceStartingWithFirstValue
 
+:::note
+This function is DEPRECATED (see the note for `runningDifference`).
+:::
+
 Same as [runningDifference](./other-functions.md#other_functions-runningdifference), but returns the value of the first row as the value on the first row.
 
 ## runningConcurrency
@@ -1930,6 +1936,7 @@ Accumulates the states of an aggregate function for each row of a data block.
 
 :::note
 The state is reset for each new block of data.
+Because of this error-prone behavior the function is DEPRECATED.
 :::
 
 **Syntax**

src/Common/ErrorCodes.cpp

@@ -598,6 +598,7 @@
     M(717, EXPERIMENTAL_FEATURE_ERROR) \
     M(718, TOO_SLOW_PARSING) \
     M(719, QUERY_CACHE_USED_WITH_SYSTEM_TABLE) \
+    M(720, DEPRECATED_FUNCTION) \
     \
     M(900, DISTRIBUTED_CACHE_ERROR) \
     M(901, CANNOT_USE_DISTRIBUTED_CACHE) \

src/Core/Settings.h

@@ -910,6 +910,7 @@ class IColumn;
     M(Int64, ignore_cold_parts_seconds, 0, "Only available in ClickHouse Cloud. Exclude new data parts from SELECT queries until they're either pre-warmed (see cache_populated_by_fetch) or this many seconds old. Only for Replicated-/SharedMergeTree.", 0) \
     M(Int64, prefer_warmed_unmerged_parts_seconds, 0, "Only available in ClickHouse Cloud. If a merged part is less than this many seconds old and is not pre-warmed (see cache_populated_by_fetch), but all its source parts are available and pre-warmed, SELECT queries will read from those parts instead. Only for ReplicatedMergeTree. Note that this only checks whether CacheWarmer processed the part; if the part was fetched into cache by something else, it'll still be considered cold until CacheWarmer gets to it; if it was warmed, then evicted from cache, it'll still be considered warm.", 0) \
     M(Bool, iceberg_engine_ignore_schema_evolution, false, "Ignore schema evolution in Iceberg table engine and read all data using latest schema saved on table creation. Note that it can lead to incorrect result", 0) \
+    M(Bool, allow_deprecated_functions, false, "Allow usage of deprecated functions", 0) \
 
 // End of COMMON_SETTINGS
 // Please add settings related to formats into the FORMAT_FACTORY_SETTINGS, move obsolete settings to OBSOLETE_SETTINGS and obsolete format settings to OBSOLETE_FORMAT_SETTINGS.

src/Core/SettingsChangesHistory.h

@@ -85,6 +85,8 @@ namespace SettingsChangesHistory
 /// It's used to implement `compatibility` setting (see https://github.com/ClickHouse/ClickHouse/issues/35972)
 static std::map<ClickHouseVersion, SettingsChangesHistory::SettingsChanges> settings_changes_history =
 {
+    {"24.5", {{"allow_deprecated_functions", true, false, "Allow usage of deprecated functions"},
+    }},
     {"24.4", {{"input_format_json_throw_on_bad_escape_sequence", true, true, "Allow to save JSON strings with bad escape sequences"},
               {"ignore_drop_queries_probability", 0, 0, "Allow to ignore drop queries in server with specified probability for testing purposes"},
               {"lightweight_deletes_sync", 2, 2, "The same as 'mutation_sync', but controls only execution of lightweight deletes"},

src/Databases/DatabaseReplicated.cpp

@@ -935,6 +935,7 @@ void DatabaseReplicated::recoverLostReplica(const ZooKeeperPtr & current_zookeep
         query_context->setSetting("allow_experimental_window_functions", 1);
         query_context->setSetting("allow_experimental_geo_types", 1);
         query_context->setSetting("allow_experimental_map_type", 1);
+        query_context->setSetting("allow_deprecated_functions", 1);
 
         query_context->setSetting("allow_suspicious_low_cardinality_types", 1);
         query_context->setSetting("allow_suspicious_fixed_string_types", 1);

src/Functions/neighbor.cpp

@@ -4,6 +4,7 @@
 #include <Functions/FunctionFactory.h>
 #include <Functions/IFunction.h>
 #include <IO/WriteHelpers.h>
+#include <Interpreters/Context.h>
 #include <Interpreters/castColumn.h>
 
 namespace DB
@@ -13,6 +14,7 @@ namespace ErrorCodes
     extern const int ILLEGAL_TYPE_OF_ARGUMENT;
     extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
     extern const int ARGUMENT_OUT_OF_BOUND;
+    extern const int DEPRECATED_FUNCTION;
 }
 
 namespace
@@ -31,7 +33,18 @@ class FunctionNeighbor : public IFunction
 {
 public:
     static constexpr auto name = "neighbor";
-    static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionNeighbor>(); }
+
+    static FunctionPtr create(ContextPtr context)
+    {
+        if (!context->getSettingsRef().allow_deprecated_functions)
+            throw Exception(
+                ErrorCodes::DEPRECATED_FUNCTION,
+                "Function {} is deprecated since its usage is error-prone (see docs)."
+                "Set `allow_deprecated_functions` setting to enable it",
+                name);
+
+        return std::make_shared<FunctionNeighbor>();
+    }
 
     /// Get the name of the function.
     String getName() const override { return name; }

src/Functions/runningAccumulate.cpp

@@ -4,6 +4,7 @@
 #include <Functions/FunctionFactory.h>
 #include <Functions/FunctionHelpers.h>
 #include <Functions/IFunction.h>
+#include <Interpreters/Context.h>
 #include <Common/AlignedBuffer.h>
 #include <Common/Arena.h>
 #include <Common/scope_guard_safe.h>
@@ -16,6 +17,7 @@ namespace ErrorCodes
     extern const int ILLEGAL_COLUMN;
     extern const int ILLEGAL_TYPE_OF_ARGUMENT;
     extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
+    extern const int DEPRECATED_FUNCTION;
 }
 
 namespace
@@ -34,8 +36,16 @@ class FunctionRunningAccumulate : public IFunction
 {
 public:
     static constexpr auto name = "runningAccumulate";
-    static FunctionPtr create(ContextPtr)
+
+    static FunctionPtr create(ContextPtr context)
     {
+        if (!context->getSettingsRef().allow_deprecated_functions)
+            throw Exception(
+                ErrorCodes::DEPRECATED_FUNCTION,
+                "Function {} is deprecated since its usage is error-prone (see docs)."
+                "Set `allow_deprecated_functions` setting to enable it",
+                name);
+
         return std::make_shared<FunctionRunningAccumulate>();
     }
 

src/Functions/runningDifference.h

@@ -1,16 +1,17 @@
 #pragma once
-#include <Functions/IFunction.h>
-#include <Functions/FunctionHelpers.h>
-#include <Columns/ColumnsNumber.h>
 #include <Columns/ColumnNullable.h>
-#include <Common/assert_cast.h>
+#include <Columns/ColumnsNumber.h>
 #include <DataTypes/DataTypeDate.h>
 #include <DataTypes/DataTypeDate32.h>
 #include <DataTypes/DataTypeDateTime.h>
 #include <DataTypes/DataTypeDateTime64.h>
+#include <DataTypes/DataTypeNullable.h>
 #include <DataTypes/DataTypesNumber.h>
 #include <DataTypes/NumberTraits.h>
-#include <DataTypes/DataTypeNullable.h>
+#include <Functions/FunctionHelpers.h>
+#include <Functions/IFunction.h>
+#include <Interpreters/Context.h>
+#include <Common/assert_cast.h>
 
 
 namespace DB
@@ -19,6 +20,7 @@ namespace DB
 namespace ErrorCodes
 {
     extern const int ILLEGAL_TYPE_OF_ARGUMENT;
+    extern const int DEPRECATED_FUNCTION;
 }
 
 
@@ -135,8 +137,15 @@ private:
 public:
     static constexpr auto name = FunctionRunningDifferenceName<is_first_line_zero>::name;
 
-    static FunctionPtr create(ContextPtr)
+    static FunctionPtr create(ContextPtr context)
     {
+        if (!context->getSettingsRef().allow_deprecated_functions)
+            throw Exception(
+                ErrorCodes::DEPRECATED_FUNCTION,
+                "Function {} is deprecated since its usage is error-prone (see docs)."
+                "Set `allow_deprecated_functions` setting to enable it",
+                name);
+
         return std::make_shared<FunctionRunningDifferenceImpl<is_first_line_zero>>();
     }
 

tests/queries/0_stateless/03131_deprecated_functions.sql

@@ -0,0 +1,13 @@
+SELECT number, neighbor(number, 2) FROM system.numbers LIMIT 10; -- { serverError 720 }
+
+SELECT runningDifference(number) FROM system.numbers LIMIT 10; -- { serverError 720 }
+
+SELECT k, runningAccumulate(sum_k) AS res FROM (SELECT number as k, sumState(k) AS sum_k FROM numbers(10) GROUP BY k ORDER BY k); -- { serverError 720 }
+
+SET allow_deprecated_functions=1;
+
+SELECT number, neighbor(number, 2) FROM system.numbers LIMIT 10 FORMAT Null;
+
+SELECT runningDifference(number) FROM system.numbers LIMIT 10 FORMAT Null;
+
+SELECT k, runningAccumulate(sum_k) AS res FROM (SELECT number as k, sumState(k) AS sum_k FROM numbers(10) GROUP BY k ORDER BY k) FORMAT Null;