core: vm: sqlvm: schema: make foreign key constraints a slice

It is allowed to declare multiple foreign key constraints on a column.

3 files changed, 52 insertions, 17 deletions

diff --git a/core/vm/sqlvm/runtime/instructions_test.go b/core/vm/sqlvm/runtime/instructions_test.go
index b316943bb..4d2e0b153 100644
--- a/core/vm/sqlvm/runtime/instructions_test.go
+++ b/core/vm/sqlvm/runtime/instructions_test.go
@@ -54,7 +54,7 @@ func createSchema(storage *common.Storage, raws []*raw) {
 		storage.Schema[1].Columns[i] = schema.NewColumn(
 			[]byte{byte(i)},
 			ast.ComposeDataType(raws[i].major, raws[i].minor),
-			0, 0, 0, 0,
+			0, nil, 0,
 		)
 	}
 	storage.Schema.SetupColumnOffset()
diff --git a/core/vm/sqlvm/schema/schema.go b/core/vm/sqlvm/schema/schema.go
index 0d40a9612..d50a3ff46 100644
--- a/core/vm/sqlvm/schema/schema.go
+++ b/core/vm/sqlvm/schema/schema.go
@@ -158,14 +158,13 @@ type Index struct {
 }
 
 type column struct {
-	Name          []byte
-	Type          ast.DataType
-	Attr          ColumnAttr
-	ForeignTable  TableRef
-	ForeignColumn ColumnRef
-	Sequence      SequenceRef
-	SlotOffset    uint8
-	ByteOffset    uint8
+	Name        []byte
+	Type        ast.DataType
+	Attr        ColumnAttr
+	ForeignKeys []ColumnDescriptor
+	Sequence    SequenceRef
+	SlotOffset  uint8
+	ByteOffset  uint8
 	// Rest is a special field reserved for use in EncodeRLP. The value stored
 	// in it will be overwritten every time EncodeRLP is called.
 	Rest interface{}
@@ -178,15 +177,14 @@ type Column struct {
 }
 
 // NewColumn return a Column instance.
-func NewColumn(Name []byte, Type ast.DataType, Attr ColumnAttr, Sequence SequenceRef,
-	FT TableRef, FC ColumnRef) Column {
+func NewColumn(Name []byte, Type ast.DataType, Attr ColumnAttr,
+	ForeignKeys []ColumnDescriptor, Sequence SequenceRef) Column {
 	c := column{
-		Name:          Name,
-		Type:          Type,
-		Attr:          Attr,
-		Sequence:      Sequence,
-		ForeignTable:  FT,
-		ForeignColumn: FC,
+		Name:        Name,
+		Type:        Type,
+		Attr:        Attr,
+		ForeignKeys: ForeignKeys,
+		Sequence:    Sequence,
 	}
 
 	return Column{
diff --git a/core/vm/sqlvm/schema/schema_test.go b/core/vm/sqlvm/schema/schema_test.go
index 0c75b0cb6..71f0ee6d3 100644
--- a/core/vm/sqlvm/schema/schema_test.go
+++ b/core/vm/sqlvm/schema/schema_test.go
@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"bytes"
 	"io/ioutil"
+	"reflect"
 	"testing"
 
 	"github.com/shopspring/decimal"
@@ -16,6 +17,39 @@ import (
 
 type SchemaTestSuite struct{ suite.Suite }
 
+func (s *SchemaTestSuite) normalizeEmptySlice(i interface{}) {
+	var process func(reflect.Type, reflect.Value)
+	process = func(t reflect.Type, v reflect.Value) {
+		switch t.Kind() {
+		case reflect.Ptr:
+			process(t.Elem(), v.Elem())
+		case reflect.Array:
+			l := v.Len()
+			for i := 0; i < l; i++ {
+				process(t.Elem(), v.Index(i))
+			}
+		case reflect.Slice:
+			if v.IsNil() {
+				s := reflect.MakeSlice(t, 0, 0)
+				v.Set(s)
+			} else {
+				l := v.Len()
+				for i := 0; i < l; i++ {
+					process(t.Elem(), v.Index(i))
+				}
+			}
+		case reflect.Struct:
+			l := t.NumField()
+			for i := 0; i < l; i++ {
+				ft := t.Field(i).Type
+				fv := v.Field(i)
+				process(ft, fv)
+			}
+		}
+	}
+	process(reflect.TypeOf(i), reflect.ValueOf(i))
+}
+
 func (s *SchemaTestSuite) requireEncodeAndDecodeColumnNoError(c Column) {
 	buffer := bytes.Buffer{}
 	w := bufio.NewWriter(&buffer)
@@ -25,6 +59,9 @@ func (s *SchemaTestSuite) requireEncodeAndDecodeColumnNoError(c Column) {
 	c2 := Column{}
 	r := ioutil.NopCloser(bufio.NewReader(&buffer))
 	s.Require().NoError(rlp.Decode(r, &c2))
+
+	s.normalizeEmptySlice(&c.column)
+	s.normalizeEmptySlice(&c2.column)
 	s.Require().Equal(c, c2)
 }