[refactor](pb) remove default value from column meta pb

be/src/storage/segment/variant/variant_writer_helpers.cpp

@@ -153,7 +153,6 @@ void init_column_meta(ColumnMetaPB* meta, uint32_t column_id, const TabletColumn
     meta->set_encoding(EncodingInfo::resolve_default_encoding(opts.storage_format, column));
     meta->set_compression(opts.compression_type);
     meta->set_is_nullable(column.is_nullable());
-    meta->set_default_value(column.default_value());
     meta->set_precision(column.precision());
     meta->set_frac(column.frac());
     if (column.has_path_info()) {

be/src/storage/segment/vertical_segment_writer.cpp

@@ -121,7 +121,6 @@ void VerticalSegmentWriter::_init_column_meta(ColumnMetaPB* meta, uint32_t colum
     meta->set_encoding(EncodingInfo::resolve_default_encoding(opts.storage_format, column));
     meta->set_compression(_opts.compression_type);
     meta->set_is_nullable(column.is_nullable());
-    meta->set_default_value(column.default_value());
     meta->set_precision(column.precision());
     meta->set_frac(column.frac());
     if (column.has_path_info()) {

gensrc/proto/segment_v2.proto

@@ -215,7 +215,7 @@ message ColumnMetaPB {
     optional ColumnPathInfo column_path_info = 13;
 
     // Extra type info to be compatible with tabet schema
-    optional bytes default_value = 14; // ColumnMessage.default_value ?
+    // optional bytes default_value = 14; // ColumnMessage.default_value, this field is useless, it is added by https://github.com/apache/doris/pull/24170/
     optional int32 precision = 15; // ColumnMessage.precision
     optional int32 frac = 16; // ColumnMessag
 

regression-test/suites/show_p0/test_show_data_warehouse.groovy

@@ -95,9 +95,11 @@ suite("test_show_data_warehouse") {
 
         boolean hitDb1 = false;
         boolean hitDb2 = false;
-
+        // Should change this value when change the segment structure, because the data size will change.
+        // This check is useful because user concern about the data size.
         long db1Size = 957 * replicaCount1
-        long db2Size = 908 * replicaCount2
+        // remove default value field from PB, the data size will be smaller than before, so we need to change the expected value.
+        long db2Size = 890 * replicaCount2
         def result;
         do {
             current = System.currentTimeMillis()