*: fix the origin_default_value issue in disaggregated mode (#9666)

dbms/src/Common/FieldVisitors.cpp

@@ -25,6 +25,14 @@
 
 namespace DB
 {
+template <typename T>
+static inline String format(const DecimalField<T> & x)
+{
+    WriteBufferFromOwnString wb;
+    writeText(x.getValue(), x.getScale(), wb);
+    return wb.str();
+}
+
 template <typename T>
 static inline String formatQuoted(T x)
 {
@@ -170,19 +178,27 @@ String FieldVisitorToString::operator()(const String & x) const
 }
 String FieldVisitorToString::operator()(const DecimalField<Decimal32> & x) const
 {
-    return formatQuoted(x);
+    if (isDecimalWithQuoted)
+        return formatQuoted(x);
+    return format(x);
 }
 String FieldVisitorToString::operator()(const DecimalField<Decimal64> & x) const
 {
-    return formatQuoted(x);
+    if (isDecimalWithQuoted)
+        return formatQuoted(x);
+    return format(x);
 }
 String FieldVisitorToString::operator()(const DecimalField<Decimal128> & x) const
 {
-    return formatQuoted(x);
+    if (isDecimalWithQuoted)
+        return formatQuoted(x);
+    return format(x);
 }
 String FieldVisitorToString::operator()(const DecimalField<Decimal256> & x) const
 {
-    return formatQuoted(x);
+    if (isDecimalWithQuoted)
+        return formatQuoted(x);
+    return format(x);
 }
 
 String FieldVisitorToString::operator()(const Array & x) const

dbms/src/Common/FieldVisitors.h

@@ -181,7 +181,16 @@ typename std::decay_t<Visitor>::ResultType applyVisitor(Visitor && visitor, F1 &
 /** Prints Field as literal in SQL query */
 class FieldVisitorToString : public StaticVisitor<String>
 {
+private:
+    bool isDecimalWithQuoted;
+
 public:
+    FieldVisitorToString()
+        : isDecimalWithQuoted(true){};
+
+    FieldVisitorToString(bool val)
+        : isDecimalWithQuoted(val){};
+
     String operator()(const Null & x) const;
     String operator()(const UInt64 & x) const;
     String operator()(const Int64 & x) const;

dbms/src/TiDB/Schema/TiDB.cpp

@@ -17,13 +17,16 @@
 #include <Common/MyTime.h>
 #include <Core/Types.h>
 #include <DataTypes/DataTypeDecimal.h>
+#include <DataTypes/FieldToDataType.h>
 #include <IO/Buffer/ReadBufferFromString.h>
 #include <Poco/Base64Decoder.h>
+#include <Poco/Dynamic/Var.h>
 #include <Poco/MemoryStream.h>
 #include <Poco/StreamCopier.h>
 #include <Poco/StringTokenizer.h>
 #include <Storages/MutableSupport.h>
 #include <TiDB/Collation/Collator.h>
+#include <TiDB/Decode/DatumCodec.h>
 #include <TiDB/Decode/JsonBinary.h>
 #include <TiDB/Decode/Vector.h>
 #include <TiDB/Schema/SchemaNameMapper.h>
@@ -36,6 +39,7 @@
 #include <algorithm>
 #include <cmath>
 #include <magic_enum.hpp>
+#include <string>
 
 namespace DB
 {
@@ -191,7 +195,8 @@ ColumnInfo::ColumnInfo(Poco::JSON::Object::Ptr json)
 Field ColumnInfo::defaultValueToField() const
 {
     const auto & value = origin_default_value;
-    if (value.isEmpty())
+    const auto & bit_value = origin_default_bit_value;
+    if (value.isEmpty() && bit_value.isEmpty())
     {
         if (hasNotNullFlag())
             return DB::GenDefaultField(*this);
@@ -223,14 +228,12 @@ Field ColumnInfo::defaultValueToField() const
         });
     case TypeBit:
     {
-        const auto & bit_value = origin_default_bit_value;
-        if (bit_value.isEmpty())
-        {
-            if (hasNotNullFlag())
-                return DB::GenDefaultField(*this);
-            return Field();
-        }
-        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({ return getBitValue(bit_value.convert<String>()); });
+        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({
+            // When we got bit_value from tipb, we have decoded it.
+            if (auto is_int = bit_value.isInteger(); is_int)
+                return bit_value.convert<UInt64>();
+            return getBitValue(bit_value.convert<String>());
+        });
     }
     // Floating type.
     case TypeFloat:
@@ -239,7 +242,12 @@ Field ColumnInfo::defaultValueToField() const
     case TypeDate:
     case TypeDatetime:
     case TypeTimestamp:
-        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({ return DB::parseMyDateTime(value.convert<String>()); });
+        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({
+            // When we got value from tipb, we have decoded it.
+            if (auto is_int = value.isInteger(); is_int)
+                return value.convert<UInt64>();
+            return DB::parseMyDateTime(value.convert<String>());
+        });
     case TypeVarchar:
     case TypeTinyBlob:
     case TypeMediumBlob:
@@ -277,12 +285,22 @@ Field ColumnInfo::defaultValueToField() const
             return getDecimalValue(text);
         });
     case TypeTime:
-        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({ return getTimeValue(value.convert<String>()); });
+        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({
+            // When we got value from tipb, we have decoded it.
+            if (auto is_int = value.isInteger(); is_int)
+                return value.convert<UInt64>();
+            return getTimeValue(value.convert<String>());
+        });
     case TypeYear:
         // Never throw exception here, do not use TRY_CATCH_DEFAULT_VALUE_TO_FIELD
         return getYearValue(value.convert<String>());
     case TypeSet:
-        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({ return getSetValue(value.convert<String>()); });
+        TRY_CATCH_DEFAULT_VALUE_TO_FIELD({
+            // When we got value from tipb, we have decoded it.
+            if (auto is_int = value.isInteger(); is_int)
+                return value.convert<UInt64>();
+            return getSetValue(value.convert<String>());
+        });
     case TypeTiDBVectorFloat32:
         return genVectorFloat32Empty();
     default:
@@ -1362,17 +1380,61 @@ ColumnInfo toTiDBColumnInfo(const tipb::ColumnInfo & tipb_column_info)
     tidb_column_info.flag = tipb_column_info.flag();
     tidb_column_info.flen = tipb_column_info.columnlen();
     tidb_column_info.decimal = tipb_column_info.decimal();
-    // TiFlash get default value from origin_default_value, check `Field ColumnInfo::defaultValueToField() const`
-    // So we need to set origin_default_value to tipb_column_info.default_val()
-    // Related logic in tidb, https://github.com/pingcap/tidb/blob/45318da24d8e4c0c6aab836d291a33f949dd18bf/pkg/table/tables/tables.go#L2303-L2329
-    // For TypeBit, we need to set origin_default_bit_value to tipb_column_info.default_val().
-    if (tidb_column_info.tp == TypeBit)
-        tidb_column_info.origin_default_bit_value = tipb_column_info.default_val();
-    else
-        tidb_column_info.origin_default_value = tipb_column_info.default_val();
     tidb_column_info.collate = tipb_column_info.collation();
     for (int i = 0; i < tipb_column_info.elems_size(); ++i)
         tidb_column_info.elems.emplace_back(tipb_column_info.elems(i), i + 1);
+    // TiFlash get default value from origin_default_value, check `Field ColumnInfo::defaultValueToField() const`
+    // So we need to set origin_default_value to tipb_column_info.default_val()
+    // Related logic in tidb, https://github.com/pingcap/tidb/blob/45318da24d8e4c0c6aab836d291a33f949dd18bf/pkg/table/tables/tables.go#L2303-L2329
+    // And, decode tipb_column_info.default_val.
+    {
+        // The default value is null.
+        if (tipb_column_info.default_val().empty())
+        {
+            Poco::Dynamic::Var empty_val;
+            tidb_column_info.origin_default_value = empty_val;
+            return tidb_column_info;
+        }
+        size_t cursor = 0;
+        auto val = DB::DecodeDatum(cursor, tipb_column_info.default_val());
+        if (val.getType() == DB::Field::Types::String)
+        {
+            tidb_column_info.origin_default_value = val.get<String>();
+            return tidb_column_info;
+        }
+        switch (tidb_column_info.tp)
+        {
+        case TypeDate:
+        case TypeDatetime:
+        case TypeTimestamp:
+        case TypeSet:
+            tidb_column_info.origin_default_value = val.get<UInt64>();
+            break;
+        case TypeTime:
+            tidb_column_info.origin_default_value = val.get<Int64>();
+            break;
+        case TypeBit:
+            // For TypeBit, we need to set origin_default_bit_value to tipb_column_info.default_val().
+            tidb_column_info.origin_default_bit_value = val.get<UInt64>();
+            break;
+        case TypeYear:
+            // If the year column has 'not null' option and the value is 0, this year value is '0000'.
+            if (val.get<Int64>() == 0)
+            {
+                Poco::Dynamic::Var empty_val;
+                tidb_column_info.origin_default_value = empty_val;
+                break;
+            }
+            // else fallthrough
+        // The above types will be processed again when defaultValueToField is called.
+        // By distinguishing the type of the string type(by synchronizing the default values in the schema, its type is string),
+        // we can distinguish whether it needs to be processed.
+        default:
+            auto str_val = DB::applyVisitor(DB::FieldVisitorToString(false), val);
+            tidb_column_info.origin_default_value = str_val;
+        }
+    }
+
     return tidb_column_info;
 }
 

tests/fullstack-test2/ddl/alter_default_value.test

@@ -103,4 +103,30 @@ mysql> set session tidb_isolation_read_engines='tiflash'; select /*+ read_from_s
 |    1 | Unprioritized |
 +------+---------------+
 
+mysql> alter table test.t drop column e;
+
+#############
+# Alter table... add column with default value
+mysql> alter table test.t add column col1 int default 30; 
+mysql> alter table test.t add column col2 year not null;
+mysql> alter table test.t add column col3 decimal(6,2) not null;
+mysql> alter table test.t add column col4 decimal(6,2) default "1.234";
+mysql> alter table test.t add column col5 int default 123;
+mysql> alter table test.t add column col6 varchar(255) default 'sss';
+mysql> alter table test.t add column col7 timestamp default '2017-02-11';
+mysql> alter table test.t add column col8 datetime default '2018-11-04 23:12:03';
+mysql> alter table test.t add column col9 year default '2012';
+mysql> alter table test.t add column col10 set('value1', 'value2', 'value3') default 'value3';
+mysql> alter table test.t add column col11 enum('value1', 'value2', 'value3') default 'value1';
+mysql> alter table test.t add column col12 datetime default '2018-11-04 23:12:03';
+mysql> alter table test.t add column col13 time default  '2017-02-23 12:18:30';
+mysql> alter table test.t add column col14 time default null;
+mysql> alter table test.t add column col15 bit(32) default b'000000010000001000000011';
+mysql> set session tidb_isolation_read_engines='tiflash'; select col1, col2, col3, col4, col5, col6, col7, col8, col9, col10, col11, col12, col13, col14, hex(col15) from test.t;
++------+------+------+------+------+------+---------------------+---------------------+------+--------+--------+---------------------+----------+-------+------------+
+| col1 | col2 | col3 | col4 | col5 | col6 | col7                | col8                | col9 | col10  | col11  | col12               | col13    | col14 | hex(col15) |
++------+------+------+------+------+------+---------------------+---------------------+------+--------+--------+---------------------+----------+-------+------------+
+|   30 | 0000 | 0.00 | 1.23 |  123 | sss  | 2017-02-11 00:00:00 | 2018-11-04 23:12:03 | 2012 | value3 | value1 | 2018-11-04 23:12:03 | 12:18:30 | NULL  | 10203      |
+|   30 | 0000 | 0.00 | 1.23 |  123 | sss  | 2017-02-11 00:00:00 | 2018-11-04 23:12:03 | 2012 | value3 | value1 | 2018-11-04 23:12:03 | 12:18:30 | NULL  | 10203      |
++------+------+------+------+------+------+---------------------+---------------------+------+--------+--------+---------------------+----------+-------+------------+
 mysql> drop table if exists test.t