diff --git a/mem/db.go b/mem/db.go
new file mode 100644
index 00000000..7638e4d5
--- /dev/null
+++ b/mem/db.go
@@ -0,0 +1,106 @@
+// Copyright © 2016 Abcum Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package mem
+
+import "github.com/abcum/surreal/sql"
+
+// --------------------------------------------------
+
+func (this *DB) GetAC(name string) *AC {
+	if ac, ok := this.AC[name]; ok {
+		return ac
+	}
+	return nil
+}
+
+func (this *DB) AddAC(ast *sql.DefineLoginStatement) {
+	if ac, ok := this.AC[ast.User]; ok {
+		ac.User = ast.User
+		ac.Pass = ast.Pass
+	} else {
+		this.AC[ast.User] = &AC{
+			User: ast.User,
+			Pass: ast.Pass,
+		}
+	}
+}
+
+// --------------------------------------------------
+
+func (this *DB) GetTK(name string) *TK {
+	if tk, ok := this.TK[name]; ok {
+		return tk
+	}
+	return nil
+}
+
+func (this *DB) AddTK(ast *sql.DefineTokenStatement) {
+	if tk, ok := this.TK[ast.Name]; ok {
+		tk.Name = ast.Name
+		tk.Text = ast.Text
+	} else {
+		this.TK[ast.Name] = &TK{
+			Name: ast.Name,
+			Text: ast.Text,
+		}
+	}
+}
+
+// --------------------------------------------------
+
+func (this *DB) GetSC(name string) *SC {
+	if sc, ok := this.SC[name]; ok {
+		return sc
+	}
+	return nil
+}
+
+func (this *DB) AddSC(ast *sql.DefineScopeStatement) {
+	if sc, ok := this.SC[ast.Name]; ok {
+		sc.Name = ast.Name
+		sc.Time = ast.Time
+		sc.Signup = ast.Signup
+		sc.Signin = ast.Signin
+	} else {
+		this.SC[ast.Name] = &SC{
+			Name:   ast.Name,
+			Time:   ast.Time,
+			Signup: ast.Signup,
+			Signin: ast.Signin,
+		}
+	}
+}
+
+// --------------------------------------------------
+
+func (this *DB) GetTB(name string) *TB {
+	if tb, ok := this.TB[name]; ok {
+		return tb
+	}
+	return nil
+}
+
+func (this *DB) AddTB(ast *sql.DefineTableStatement) {
+	for _, name := range ast.What {
+		if tb, ok := this.TB[name]; ok {
+			tb.Name = name
+		} else {
+			this.TB[name] = &TB{
+				Name: name,
+				FD:   make(map[string]*FD),
+			}
+		}
+	}
+}
diff --git a/mem/kv.go b/mem/kv.go
new file mode 100644
index 00000000..e95e6876
--- /dev/null
+++ b/mem/kv.go
@@ -0,0 +1,39 @@
+// Copyright © 2016 Abcum Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package mem
+
+import "github.com/abcum/surreal/sql"
+
+// --------------------------------------------------
+
+func GetNS(name string) *NS {
+	if ns, ok := store[name]; ok {
+		return ns
+	}
+	return nil
+}
+
+func AddNS(ast *sql.DefineNamespaceStatement) {
+	if ns, ok := store[ast.Name]; ok {
+		ns.Name = ast.Name
+	} else {
+		store[ast.Name] = &NS{
+			Name: ast.Name,
+			AC:   make(map[string]*AC),
+			TK:   make(map[string]*TK),
+			DB:   make(map[string]*DB),
+		}
+	}
+}
diff --git a/mem/mem.go b/mem/mem.go
new file mode 100644
index 00000000..52f65fc5
--- /dev/null
+++ b/mem/mem.go
@@ -0,0 +1,90 @@
+// Copyright © 2016 Abcum Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package mem
+
+import (
+	"time"
+
+	"github.com/abcum/surreal/sql"
+)
+
+var store map[string]*NS
+
+type NS struct {
+	AC   map[string]*AC
+	TK   map[string]*TK
+	DB   map[string]*DB
+	Name string
+}
+
+type DB struct {
+	AC   map[string]*AC
+	TK   map[string]*TK
+	SC   map[string]*SC
+	TB   map[string]*TB
+	Name string
+}
+
+type TB struct {
+	FD   map[string]*FD
+	IX   map[string]*IX
+	Name string
+}
+
+type AC struct {
+	User string
+	Pass string
+	Uniq string
+}
+
+type TK struct {
+	Name string
+	Type string
+	Text string
+}
+
+type SC struct {
+	TK     map[string]*TK
+	Name   string
+	Uniq   string
+	Time   time.Duration
+	Signup sql.Expr
+	Signin sql.Expr
+}
+
+type FD struct {
+	Name      string
+	Type      string
+	Enum      []interface{}
+	Code      string
+	Min       float64
+	Max       float64
+	Match     string
+	Default   interface{}
+	Notnull   bool
+	Readonly  bool
+	Mandatory bool
+	Validate  bool
+}
+
+type IX struct {
+	Name string
+	Cols []string
+	Uniq bool
+}
+
+func init() {
+	store = make(map[string]*NS)
+}
diff --git a/mem/ns.go b/mem/ns.go
new file mode 100644
index 00000000..dca1c67b
--- /dev/null
+++ b/mem/ns.go
@@ -0,0 +1,82 @@
+// Copyright © 2016 Abcum Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package mem
+
+import "github.com/abcum/surreal/sql"
+
+// --------------------------------------------------
+
+func (this *NS) GetAC(name string) *AC {
+	if ac, ok := this.AC[name]; ok {
+		return ac
+	}
+	return nil
+}
+
+func (this *NS) AddAC(ast *sql.DefineLoginStatement) {
+	if ac, ok := this.AC[ast.User]; ok {
+		ac.User = ast.User
+		ac.Pass = ast.Pass
+	} else {
+		this.AC[ast.User] = &AC{
+			User: ast.User,
+			Pass: ast.Pass,
+		}
+	}
+}
+
+// --------------------------------------------------
+
+func (this *NS) GetTK(name string) *TK {
+	if tk, ok := this.TK[name]; ok {
+		return tk
+	}
+	return nil
+}
+
+func (this *NS) AddTK(ast *sql.DefineTokenStatement) {
+	if tk, ok := this.TK[ast.Name]; ok {
+		tk.Name = ast.Name
+		tk.Text = ast.Text
+	} else {
+		this.TK[ast.Name] = &TK{
+			Name: ast.Name,
+			Text: ast.Text,
+		}
+	}
+}
+
+// --------------------------------------------------
+
+func (this *NS) GetDB(name string) *DB {
+	if db, ok := this.DB[name]; ok {
+		return db
+	}
+	return nil
+}
+
+func (this *NS) AddDB(ast *sql.DefineDatabaseStatement) {
+	if db, ok := this.DB[ast.Name]; ok {
+		db.Name = ast.Name
+	} else {
+		this.DB[ast.Name] = &DB{
+			Name: ast.Name,
+			AC:   make(map[string]*AC),
+			TK:   make(map[string]*TK),
+			SC:   make(map[string]*SC),
+			TB:   make(map[string]*TB),
+		}
+	}
+}
diff --git a/mem/sc.go b/mem/sc.go
new file mode 100644
index 00000000..31775987
--- /dev/null
+++ b/mem/sc.go
@@ -0,0 +1,38 @@
+// Copyright © 2016 Abcum Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package mem
+
+import "github.com/abcum/surreal/sql"
+
+// --------------------------------------------------
+
+func (this *SC) GetTK(name string) *TK {
+	if tk, ok := this.TK[name]; ok {
+		return tk
+	}
+	return nil
+}
+
+func (this *SC) AddTK(ast *sql.DefineTokenStatement) {
+	if tk, ok := this.TK[ast.Name]; ok {
+		tk.Name = ast.Name
+		tk.Text = ast.Text
+	} else {
+		this.TK[ast.Name] = &TK{
+			Name: ast.Name,
+			Text: ast.Text,
+		}
+	}
+}
diff --git a/mem/tb.go b/mem/tb.go
new file mode 100644
index 00000000..1e821cc8
--- /dev/null
+++ b/mem/tb.go
@@ -0,0 +1,81 @@
+// Copyright © 2016 Abcum Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package mem
+
+import "github.com/abcum/surreal/sql"
+
+// --------------------------------------------------
+
+func (this *TB) GetFD(name string) *FD {
+	if fd, ok := this.FD[name]; ok {
+		return fd
+	}
+	return nil
+}
+
+func (this *TB) AddFD(ast *sql.DefineFieldStatement) {
+	if fd, ok := this.FD[ast.Name]; ok {
+		fd.Name = ast.Name
+		fd.Type = ast.Type
+		fd.Enum = ast.Enum
+		fd.Code = ast.Code
+		fd.Min = ast.Min
+		fd.Max = ast.Max
+		fd.Match = ast.Match
+		fd.Default = ast.Default
+		fd.Notnull = ast.Notnull
+		fd.Readonly = ast.Readonly
+		fd.Mandatory = ast.Mandatory
+		fd.Validate = ast.Validate
+	} else {
+		this.FD[ast.Name] = &FD{
+			Name:      ast.Name,
+			Type:      ast.Type,
+			Enum:      ast.Enum,
+			Code:      ast.Code,
+			Min:       ast.Min,
+			Max:       ast.Max,
+			Match:     ast.Match,
+			Default:   ast.Default,
+			Notnull:   ast.Notnull,
+			Readonly:  ast.Readonly,
+			Mandatory: ast.Mandatory,
+			Validate:  ast.Validate,
+		}
+	}
+}
+
+// --------------------------------------------------
+
+func (this *TB) GetIX(name string) *IX {
+	if ix, ok := this.IX[name]; ok {
+		return ix
+	}
+	return nil
+}
+
+func (this *TB) AdIX(ast *sql.DefineIndexStatement) {
+	if ix, ok := this.IX[ast.Name]; ok {
+		ix.Name = ast.Name
+		ix.Cols = ast.Cols
+		ix.Uniq = ast.Uniq
+	} else {
+		this.IX[ast.Name] = &IX{
+			Name: ast.Name,
+			Cols: ast.Cols,
+			Uniq: ast.Uniq,
+		}
+	}
+}