Repro test

tests/queries/0_stateless/02967_prewhere_no_columns.reference

@@ -0,0 +1,2 @@
+105
+105

tests/queries/0_stateless/02967_prewhere_no_columns.sql

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+CREATE TABLE t_02967
+(
+  `key` Date,
+  `value` UInt16
+)
+ENGINE = MergeTree
+ORDER BY key
+SETTINGS
+  index_granularity_bytes = 0 --8192 --, min_index_granularity_bytes = 2  
+ , index_granularity = 100
+ , min_rows_for_wide_part = 0, min_bytes_for_wide_part = 0
+--
+--  , min_bytes_for_wide_part = 2
+AS SELECT
+  number,
+  repeat(toString(number), 5)
+FROM numbers(105.);
+
+
+
+-- Check with newly inserted data part. It's in-memory structured are filled at insert time.
+SELECT
+  count(ignore(*))
+FROM t_02967
+PREWHERE CAST(ignore() + 1 as UInt8)
+GROUP BY 
+  ignore(65535, *),
+  ignore(255, 256, *)
+SETTINGS
+ --send_logs_level='test', 
+ max_threads=1;
+
+
+
+-- Reload part form disk to check that in-meory structures where properly serilaized-deserialized
+DETACH TABLE t_02967;
+ATTACH TABLE t_02967;
+
+
+SELECT
+  count(ignore(*))
+FROM t_02967
+PREWHERE CAST(ignore() + 1 as UInt8)
+GROUP BY 
+  ignore(65535, *),
+  ignore(255, 256, *)
+SETTINGS
+ --send_logs_level='test', 
+ max_threads=1;
+
+DROP TABLE t_02967;