diff --git a/cmd/gemini/schema.json b/cmd/gemini/schema.json
index eb95a090..2bb3c6f3 100644
--- a/cmd/gemini/schema.json
+++ b/cmd/gemini/schema.json
@@ -29,14 +29,14 @@
         {
           "name": "col0",
           "type": {
-            "types": {
+            "type_name": "udt_672245080",
+            "frozen": true,
+            "coltypes": {
               "udt_672245080_0": "ascii",
               "udt_672245080_1": "boolean",
               "udt_672245080_2": "bigint",
               "udt_672245080_3": "blob"
-            },
-            "type_name": "udt_672245080",
-            "frozen": true
+            }
           }
         },
         {
diff --git a/pkg/joberror/joberror.go b/pkg/joberror/joberror.go
index 1558440a..8ea5588b 100644
--- a/pkg/joberror/joberror.go
+++ b/pkg/joberror/joberror.go
@@ -25,6 +25,7 @@ type JobError struct {
 	Timestamp time.Time `json:"timestamp"`
 	Message   string    `json:"message"`
 	Query     string    `json:"query"`
+	StmtType  string    `json:"stmt-type"`
 }
 
 type ErrorList struct {
diff --git a/pkg/jobs/gen_ddl_stmt.go b/pkg/jobs/gen_ddl_stmt.go
index c05e735e..2d2837e4 100644
--- a/pkg/jobs/gen_ddl_stmt.go
+++ b/pkg/jobs/gen_ddl_stmt.go
@@ -73,7 +73,8 @@ func genAddColumnStmt(t *typedef.Table, keyspace string, column *typedef.ColumnD
 		},
 	})
 	return &typedef.Stmts{
-		List: stmts,
+		List:      stmts,
+		QueryType: typedef.AddColumnStatementType,
 		PostStmtHook: func() {
 			t.Columns = append(t.Columns, column)
 			t.ResetQueryCache()
@@ -124,7 +125,8 @@ func genDropColumnStmt(t *typedef.Table, keyspace string, column *typedef.Column
 		},
 	})
 	return &typedef.Stmts{
-		List: stmts,
+		List:      stmts,
+		QueryType: typedef.DropColumnStatementType,
 		PostStmtHook: func() {
 			t.Columns = t.Columns.Remove(column)
 			t.ResetQueryCache()
diff --git a/pkg/jobs/gen_mutate_stmt.go b/pkg/jobs/gen_mutate_stmt.go
index 07283c1e..36f6363b 100644
--- a/pkg/jobs/gen_mutate_stmt.go
+++ b/pkg/jobs/gen_mutate_stmt.go
@@ -174,7 +174,7 @@ func genInsertJSONStmt(
 		StmtCache: &typedef.StmtCache{
 			Query:     builder,
 			Types:     []typedef.Type{typedef.TYPE_TEXT},
-			QueryType: typedef.InsertStatement,
+			QueryType: typedef.InsertJSONStatementType,
 		},
 		ValuesWithToken: valuesWithToken,
 		Values:          []interface{}{string(jsonString)},
diff --git a/pkg/jobs/jobs.go b/pkg/jobs/jobs.go
index 6a341f73..cf503a93 100644
--- a/pkg/jobs/jobs.go
+++ b/pkg/jobs/jobs.go
@@ -243,6 +243,7 @@ func validationJob(
 			if err := validation(ctx, schemaConfig, table, s, stmt, g, globalStatus, logger); err != nil {
 				globalStatus.AddReadError(&joberror.JobError{
 					Timestamp: time.Now(),
+					StmtType:  stmt.QueryType.ToString(),
 					Message:   "Validation failed: " + err.Error(),
 					Query:     stmt.PrettyCQL(),
 				})
@@ -341,6 +342,7 @@ func ddl(
 		if err = s.Mutate(ctx, ddlStmt.Query); err != nil {
 			globalStatus.AddWriteError(&joberror.JobError{
 				Timestamp: time.Now(),
+				StmtType:  ddlStmts.QueryType.ToString(),
 				Message:   "DDL failed: " + err.Error(),
 				Query:     ddlStmt.PrettyCQL(),
 			})
@@ -394,6 +396,7 @@ func mutation(
 	if err = s.Mutate(ctx, mutateQuery, mutateValues...); err != nil {
 		globalStatus.AddWriteError(&joberror.JobError{
 			Timestamp: time.Now(),
+			StmtType:  mutateStmt.QueryType.ToString(),
 			Message:   "Mutation failed: " + err.Error(),
 			Query:     mutateStmt.PrettyCQL(),
 		})
diff --git a/pkg/querycache/querycache.go b/pkg/querycache/querycache.go
index e0c40b16..b69d29c7 100644
--- a/pkg/querycache/querycache.go
+++ b/pkg/querycache/querycache.go
@@ -123,7 +123,7 @@ func genInsertStmtCache(
 	return &typedef.StmtCache{
 		Query:     builder,
 		Types:     allTypes,
-		QueryType: typedef.InsertStatement,
+		QueryType: typedef.InsertStatementType,
 	}
 }
 
@@ -164,7 +164,7 @@ func genUpdateStmtCache(s *typedef.Schema, t *typedef.Table) *typedef.StmtCache
 	return &typedef.StmtCache{
 		Query:     builder,
 		Types:     allTypes,
-		QueryType: typedef.Updatetatement,
+		QueryType: typedef.UpdateStatementType,
 	}
 }
 
diff --git a/pkg/store/cqlstore.go b/pkg/store/cqlstore.go
index 1951c797..c277f0d8 100644
--- a/pkg/store/cqlstore.go
+++ b/pkg/store/cqlstore.go
@@ -140,8 +140,8 @@ func ignore(err error) bool {
 		return true
 	}
 	//nolint:errorlint
-	switch err {
-	case context.Canceled, context.DeadlineExceeded:
+	switch {
+	case errors.Is(err, context.Canceled), errors.Is(err, context.DeadlineExceeded):
 		return true
 	default:
 		return false
diff --git a/pkg/typedef/bag.go b/pkg/typedef/bag.go
index 65fd1b25..bc596254 100644
--- a/pkg/typedef/bag.go
+++ b/pkg/typedef/bag.go
@@ -87,6 +87,15 @@ func (ct *BagType) GenValue(r *rand.Rand, p *PartitionRangeConfig) []interface{}
 	return []interface{}{out}
 }
 
+func (ct *BagType) GenJSONValue(r *rand.Rand, p *PartitionRangeConfig) interface{} {
+	count := r.Intn(9) + 1
+	out := make([]interface{}, count)
+	for i := 0; i < count; i++ {
+		out[i] = ct.Type.GenJSONValue(r, p)
+	}
+	return out
+}
+
 func (ct *BagType) LenValue() int {
 	return 1
 }
diff --git a/pkg/typedef/columns.go b/pkg/typedef/columns.go
index 6bf02d04..fc1525df 100644
--- a/pkg/typedef/columns.go
+++ b/pkg/typedef/columns.go
@@ -16,7 +16,6 @@ package typedef
 
 import (
 	"encoding/json"
-	"fmt"
 
 	"github.com/mitchellh/mapstructure"
 	"github.com/pkg/errors"
@@ -96,31 +95,7 @@ func (c Columns) Remove(column *ColumnDef) Columns {
 
 func (c Columns) ToJSONMap(values map[string]interface{}, r *rand.Rand, p *PartitionRangeConfig) map[string]interface{} {
 	for _, k := range c {
-		switch t := k.Type.(type) {
-		case SimpleType:
-			if t != TYPE_BLOB {
-				values[k.Name] = t.GenValue(r, p)[0]
-				continue
-			}
-			v, ok := t.GenValue(r, p)[0].(string)
-			if ok {
-				values[k.Name] = "0x" + v
-			}
-		case *TupleType:
-			vv := t.GenValue(r, p)
-			for i, val := range vv {
-				if t.Types[i] == TYPE_BLOB {
-					v, ok := val.(string)
-					if ok {
-						v = "0x" + v
-					}
-					vv[i] = v
-				}
-			}
-			values[k.Name] = vv
-		default:
-			panic(fmt.Sprintf("unknown type: %s", t.Name()))
-		}
+		values[k.Name] = k.Type.GenJSONValue(r, p)
 	}
 	return values
 }
diff --git a/pkg/typedef/const.go b/pkg/typedef/const.go
index 5534b4ca..b61befe2 100644
--- a/pkg/typedef/const.go
+++ b/pkg/typedef/const.go
@@ -30,10 +30,12 @@ const (
 	SelectByIndexStatementType
 	SelectFromMaterializedViewStatementType
 	DeleteStatementType
-	InsertStatement
-	Updatetatement
+	InsertStatementType
+	InsertJSONStatementType
+	UpdateStatementType
 	AlterColumnStatementType
 	DropColumnStatementType
+	AddColumnStatementType
 )
 
 //nolint:revive
diff --git a/pkg/typedef/interfaces.go b/pkg/typedef/interfaces.go
index ae9c476c..c362ce0c 100644
--- a/pkg/typedef/interfaces.go
+++ b/pkg/typedef/interfaces.go
@@ -25,6 +25,7 @@ type Type interface {
 	CQLHolder() string
 	CQLPretty(string, []interface{}) (string, int)
 	GenValue(*rand.Rand, *PartitionRangeConfig) []interface{}
+	GenJSONValue(*rand.Rand, *PartitionRangeConfig) interface{}
 	LenValue() int
 	Indexable() bool
 	CQLType() gocql.TypeInfo
diff --git a/pkg/typedef/simple_type.go b/pkg/typedef/simple_type.go
index ae0da6fb..99fba24b 100644
--- a/pkg/typedef/simple_type.go
+++ b/pkg/typedef/simple_type.go
@@ -156,49 +156,57 @@ func (st SimpleType) Indexable() bool {
 	return st != TYPE_DURATION
 }
 
+func (st SimpleType) GenJSONValue(r *rand.Rand, p *PartitionRangeConfig) interface{} {
+	if st == TYPE_BLOB {
+		ln := r.Intn(p.MaxBlobLength) + p.MinBlobLength
+		return "0x" + hex.EncodeToString([]byte(utils.RandString(r, ln)))
+	}
+	return st.genValue(r, p)
+}
+
 func (st SimpleType) GenValue(r *rand.Rand, p *PartitionRangeConfig) []interface{} {
-	var val interface{}
+	return []interface{}{st.genValue(r, p)}
+}
+
+func (st SimpleType) genValue(r *rand.Rand, p *PartitionRangeConfig) interface{} {
 	switch st {
 	case TYPE_ASCII, TYPE_TEXT, TYPE_VARCHAR:
 		ln := r.Intn(p.MaxStringLength) + p.MinStringLength
-		val = utils.RandString(r, ln)
+		return utils.RandString(r, ln)
 	case TYPE_BLOB:
 		ln := r.Intn(p.MaxBlobLength) + p.MinBlobLength
-		val = hex.EncodeToString([]byte(utils.RandString(r, ln)))
+		return hex.EncodeToString([]byte(utils.RandString(r, ln)))
 	case TYPE_BIGINT:
-		val = r.Int63()
+		return r.Int63()
 	case TYPE_BOOLEAN:
-		val = r.Int()%2 == 0
+		return r.Int()%2 == 0
 	case TYPE_DATE:
-		val = utils.RandDate(r)
+		return utils.RandDate(r)
 	case TYPE_TIME:
-		val = utils.RandTime(r).UnixNano()
+		return utils.RandTime(r).UnixNano()
 	case TYPE_TIMESTAMP:
-		val = utils.RandTime(r)
+		return utils.RandTime(r)
 	case TYPE_DECIMAL:
-		val = inf.NewDec(r.Int63(), 3)
+		return inf.NewDec(r.Int63(), 3)
 	case TYPE_DOUBLE:
-		val = r.Float64()
+		return r.Float64()
 	case TYPE_DURATION:
-		val = (time.Minute * time.Duration(r.Intn(100))).String()
+		return (time.Minute * time.Duration(r.Intn(100))).String()
 	case TYPE_FLOAT:
-		val = r.Float32()
+		return r.Float32()
 	case TYPE_INET:
-		val = net.ParseIP(utils.RandIPV4Address(r, r.Intn(255), 2)).String()
+		return net.ParseIP(utils.RandIPV4Address(r, r.Intn(255), 2)).String()
 	case TYPE_INT:
-		val = r.Int31()
+		return r.Int31()
 	case TYPE_SMALLINT:
-		val = int16(r.Int31())
+		return int16(r.Int31())
 	case TYPE_TIMEUUID, TYPE_UUID:
-		val = utils.UUIDFromTime(r)
+		return utils.UUIDFromTime(r)
 	case TYPE_TINYINT:
-		val = int8(r.Int31())
+		return int8(r.Int31())
 	case TYPE_VARINT:
-		val = big.NewInt(r.Int63())
+		return big.NewInt(r.Int63())
 	default:
 		panic(fmt.Sprintf("generate value: not supported type %s", st))
 	}
-	return []interface{}{
-		val,
-	}
 }
diff --git a/pkg/typedef/tuple.go b/pkg/typedef/tuple.go
index 25cb134c..cc05a4b1 100644
--- a/pkg/typedef/tuple.go
+++ b/pkg/typedef/tuple.go
@@ -74,6 +74,14 @@ func (t *TupleType) Indexable() bool {
 	return true
 }
 
+func (t *TupleType) GenJSONValue(r *rand.Rand, p *PartitionRangeConfig) interface{} {
+	out := make([]interface{}, 0, len(t.Types))
+	for _, tp := range t.Types {
+		out = append(out, tp.GenJSONValue(r, p))
+	}
+	return out
+}
+
 func (t *TupleType) GenValue(r *rand.Rand, p *PartitionRangeConfig) []interface{} {
 	out := make([]interface{}, 0, len(t.Types))
 	for _, tp := range t.Types {
diff --git a/pkg/typedef/typedef.go b/pkg/typedef/typedef.go
index bdbda6ab..6ecf5c8d 100644
--- a/pkg/typedef/typedef.go
+++ b/pkg/typedef/typedef.go
@@ -52,6 +52,7 @@ type (
 type Stmts struct {
 	PostStmtHook func()
 	List         []*Stmt
+	QueryType    StatementType
 }
 
 type StmtCache struct {
@@ -87,6 +88,35 @@ func (s *Stmt) PrettyCQL() string {
 
 type StatementType uint8
 
+func (st StatementType) ToString() string {
+	switch st {
+	case SelectStatementType:
+		return "SelectStatement"
+	case SelectRangeStatementType:
+		return "SelectRangeStatement"
+	case SelectByIndexStatementType:
+		return "SelectByIndexStatement"
+	case SelectFromMaterializedViewStatementType:
+		return "SelectFromMaterializedViewStatement"
+	case DeleteStatementType:
+		return "DeleteStatement"
+	case InsertStatementType:
+		return "InsertStatement"
+	case InsertJSONStatementType:
+		return "InsertJSONStatement"
+	case UpdateStatementType:
+		return "UpdateStatement"
+	case AlterColumnStatementType:
+		return "AlterColumnStatement"
+	case DropColumnStatementType:
+		return "DropColumnStatement"
+	case AddColumnStatementType:
+		return "AddColumnStatement"
+	default:
+		panic(fmt.Sprintf("unknown statement type %d", st))
+	}
+}
+
 func (st StatementType) PossibleAsyncOperation() bool {
 	switch st {
 	case SelectByIndexStatementType, SelectFromMaterializedViewStatementType:
diff --git a/pkg/typedef/types.go b/pkg/typedef/types.go
index d59a8728..864566ec 100644
--- a/pkg/typedef/types.go
+++ b/pkg/typedef/types.go
@@ -135,6 +135,15 @@ func (mt *MapType) CQLPretty(query string, value []interface{}) (string, int) {
 	return strings.Replace(query, "?", vv, 1), 1
 }
 
+func (mt *MapType) GenJSONValue(r *rand.Rand, p *PartitionRangeConfig) interface{} {
+	count := r.Intn(9) + 1
+	vals := make(map[interface{}]interface{})
+	for i := 0; i < count; i++ {
+		vals[mt.KeyType.GenJSONValue(r, p)] = mt.ValueType.GenJSONValue(r, p)
+	}
+	return vals
+}
+
 func (mt *MapType) GenValue(r *rand.Rand, p *PartitionRangeConfig) []interface{} {
 	count := r.Intn(9) + 1
 	vals := make(map[interface{}]interface{})
@@ -179,6 +188,13 @@ func (ct *CounterType) CQLPretty(query string, value []interface{}) (string, int
 	return strings.Replace(query, "?", fmt.Sprintf("%d", value[0]), 1), 1
 }
 
+func (ct *CounterType) GenJSONValue(r *rand.Rand, _ *PartitionRangeConfig) interface{} {
+	if utils.UnderTest {
+		return r.Int63()
+	}
+	return atomic.AddInt64(&ct.Value, 1)
+}
+
 func (ct *CounterType) GenValue(r *rand.Rand, _ *PartitionRangeConfig) []interface{} {
 	if utils.UnderTest {
 		return []interface{}{r.Int63()}
diff --git a/pkg/typedef/udt.go b/pkg/typedef/udt.go
index b4e3d16c..8d0749e4 100644
--- a/pkg/typedef/udt.go
+++ b/pkg/typedef/udt.go
@@ -73,6 +73,14 @@ func (t *UDTType) Indexable() bool {
 	return true
 }
 
+func (t *UDTType) GenJSONValue(r *rand.Rand, p *PartitionRangeConfig) interface{} {
+	vals := make(map[string]interface{})
+	for name, typ := range t.Types {
+		vals[name] = typ.GenJSONValue(r, p)
+	}
+	return vals
+}
+
 func (t *UDTType) GenValue(r *rand.Rand, p *PartitionRangeConfig) []interface{} {
 	vals := make(map[string]interface{})
 	for name, typ := range t.Types {