diff --git a/README.fr.md b/README.fr.md
index e55976c..ccd6b73 100644
--- a/README.fr.md
+++ b/README.fr.md
@@ -54,128 +54,135 @@ database-anonymizer --dsn "postgres://postgres:postgres@localhost:5432/test" --s
 
 ### Liste des générateurs
 
-- address
-- address_buildingnumber
-- address_city
-- address_cityprefix
-- address_citysuffix
-- address_country
-- address_countryabbr
-- address_countrycode
-- address_latitude
-- address_longitude
-- address_postcode
-- address_secondaryaddress
-- address_state
-- address_stateabbr
-- address_streetaddress
-- address_streetname
-- address_streetsuffix
-- app_name
-- app_version
-- beer_alcohol
-- beer_blg
-- beer_hop
-- beer_ibu
-- beer_malt
-- beer_name
-- beer_style
-- blood_name
-- boolean_bool
-- car_category
-- car_fueltype
-- car_maker
-- car_model
-- car_plate
-- car_transmissiongear
-- color_css
-- color_colorname
-- color_hex
-- color_rgb
-- color_safecolorname
-- company_bs
-- company_catchphrase
-- company_ein
-- company_jobtitle
-- company_name
-- company_suffix
-- crypto_bech32address
-- crypto_bitcoinaddress
-- crypto_etheriumaddress
-- crypto_p2pkhaddress
-- crypto_p2shaddress
-- currency_code
-- currency_country
-- currency_currency
-- currency_number
-- emoji_emoji
-- emoji_emojicode
-- file_extension
-- file_filenamewithextension
-- food_fruit
-- food_vegetable
-- gamer_tag
-- gender_abbr
-- gender_name
-- genre_name
-- internet_companyemail
-- internet_domain
-- internet_email
-- internet_freeemail
-- internet_freeemaildomain
-- internet_httpmethod
-- internet_ipv4
-- internet_ipv6
-- internet_localipv4
-- internet_macaddress
-- internet_password
-- internet_query
-- internet_safeemail
-- internet_slug
-- internet_statuscode
-- internet_statuscodemessage
-- internet_statuscodewithmessage
-- internet_tld
-- internet_url
-- internet_user
-- language_language
-- language_languageabbr
-- language_programminglanguage
-- mimetype_mimetype
-- music_genre
-- music_name
-- payment_creditcardexpirationdatestring
-- payment_creditcardnumber
-- payment_creditcardtype
-- person_firstname
-- person_firstnamefemale
-- person_firstnamemale
-- person_gender
-- person_lastname
-- person_name
-- person_namefemale
-- person_namemale
-- person_ssn
-- person_suffix
-- person_title
-- pet_cat
-- pet_dog
-- pet_name
-- phone_areacode
-- phone_e164number
-- phone_exchangecode
-- phone_number
-- phone_tollfreeareacode
-- phone_toolfreenumber
-- time_ampm
-- time_century
-- time_dayofmonth
-- time_monthname
-- time_timezone
-- time_year
-- useragent_chrome
-- useragent_firefox
-- useragent_internetexplorer
-- useragent_opera
-- useragent_safari
-- useragent_useragent
+#### Générateurs spéciaux
+
+- `"null"` : remplace la valeur par `null`
+- `""` ou `"_"`: n'applique aucun changement
+
+#### Les autres
+
+- `"address"`
+- `"address_buildingnumber"`
+- `"address_city"`
+- `"address_cityprefix"`
+- `"address_citysuffix"`
+- `"address_country"`
+- `"address_countryabbr"`
+- `"address_countrycode"`
+- `"address_latitude"`
+- `"address_longitude"`
+- `"address_postcode"`
+- `"address_secondaryaddress"`
+- `"address_state"`
+- `"address_stateabbr"`
+- `"address_streetaddress"`
+- `"address_streetname"`
+- `"address_streetsuffix"`
+- `"app_name"`
+- `"app_version"`
+- `"beer_alcohol"`
+- `"beer_blg"`
+- `"beer_hop"`
+- `"beer_ibu"`
+- `"beer_malt"`
+- `"beer_name"`
+- `"beer_style"`
+- `"blood_name"`
+- `"boolean_bool"`
+- `"car_category"`
+- `"car_fueltype"`
+- `"car_maker"`
+- `"car_model"`
+- `"car_plate"`
+- `"car_transmissiongear"`
+- `"color_css"`
+- `"color_colorname"`
+- `"color_hex"`
+- `"color_rgb"`
+- `"color_safecolorname"`
+- `"company_bs"`
+- `"company_catchphrase"`
+- `"company_ein"`
+- `"company_jobtitle"`
+- `"company_name"`
+- `"company_suffix"`
+- `"crypto_bech32address"`
+- `"crypto_bitcoinaddress"`
+- `"crypto_etheriumaddress"`
+- `"crypto_p2pkhaddress"`
+- `"crypto_p2shaddress"`
+- `"currency_code"`
+- `"currency_country"`
+- `"currency_currency"`
+- `"currency_number"`
+- `"emoji_emoji"`
+- `"emoji_emojicode"`
+- `"file_extension"`
+- `"file_filenamewithextension"`
+- `"food_fruit"`
+- `"food_vegetable"`
+- `"gamer_tag"`
+- `"gender_abbr"`
+- `"gender_name"`
+- `"genre_name"`
+- `"internet_companyemail"`
+- `"internet_domain"`
+- `"internet_email"`
+- `"internet_freeemail"`
+- `"internet_freeemaildomain"`
+- `"internet_httpmethod"`
+- `"internet_ipv4"`
+- `"internet_ipv6"`
+- `"internet_localipv4"`
+- `"internet_macaddress"`
+- `"internet_password"`
+- `"internet_query"`
+- `"internet_safeemail"`
+- `"internet_slug"`
+- `"internet_statuscode"`
+- `"internet_statuscodemessage"`
+- `"internet_statuscodewithmessage"`
+- `"internet_tld"`
+- `"internet_url"`
+- `"internet_user"`
+- `"language_language"`
+- `"language_languageabbr"`
+- `"language_programminglanguage"`
+- `"mimetype_mimetype"`
+- `"music_genre"`
+- `"music_name"`
+- `"payment_creditcardexpirationdatestring"`
+- `"payment_creditcardnumber"`
+- `"payment_creditcardtype"`
+- `"person_firstname"`
+- `"person_firstnamefemale"`
+- `"person_firstnamemale"`
+- `"person_gender"`
+- `"person_lastname"`
+- `"person_name"`
+- `"person_namefemale"`
+- `"person_namemale"`
+- `"person_ssn"`
+- `"person_suffix"`
+- `"person_title"`
+- `"pet_cat"`
+- `"pet_dog"`
+- `"pet_name"`
+- `"phone_areacode"`
+- `"phone_e164number"`
+- `"phone_exchangecode"`
+- `"phone_number"`
+- `"phone_tollfreeareacode"`
+- `"phone_toolfreenumber"`
+- `"time_ampm"`
+- `"time_century"`
+- `"time_dayofmonth"`
+- `"time_monthname"`
+- `"time_timezone"`
+- `"time_year"`
+- `"useragent_chrome"`
+- `"useragent_firefox"`
+- `"useragent_internetexplorer"`
+- `"useragent_opera"`
+- `"useragent_safari"`
+- `"useragent_useragent"`
diff --git a/README.md b/README.md
index cc7c737..b3b4fea 100644
--- a/README.md
+++ b/README.md
@@ -54,128 +54,135 @@ database-anonymizer --dsn "postgres://postgres:postgres@localhost:5432/test" --s
 
 ### List of fakers
 
-- address
-- address_buildingnumber
-- address_city
-- address_cityprefix
-- address_citysuffix
-- address_country
-- address_countryabbr
-- address_countrycode
-- address_latitude
-- address_longitude
-- address_postcode
-- address_secondaryaddress
-- address_state
-- address_stateabbr
-- address_streetaddress
-- address_streetname
-- address_streetsuffix
-- app_name
-- app_version
-- beer_alcohol
-- beer_blg
-- beer_hop
-- beer_ibu
-- beer_malt
-- beer_name
-- beer_style
-- blood_name
-- boolean_bool
-- car_category
-- car_fueltype
-- car_maker
-- car_model
-- car_plate
-- car_transmissiongear
-- color_css
-- color_colorname
-- color_hex
-- color_rgb
-- color_safecolorname
-- company_bs
-- company_catchphrase
-- company_ein
-- company_jobtitle
-- company_name
-- company_suffix
-- crypto_bech32address
-- crypto_bitcoinaddress
-- crypto_etheriumaddress
-- crypto_p2pkhaddress
-- crypto_p2shaddress
-- currency_code
-- currency_country
-- currency_currency
-- currency_number
-- emoji_emoji
-- emoji_emojicode
-- file_extension
-- file_filenamewithextension
-- food_fruit
-- food_vegetable
-- gamer_tag
-- gender_abbr
-- gender_name
-- genre_name
-- internet_companyemail
-- internet_domain
-- internet_email
-- internet_freeemail
-- internet_freeemaildomain
-- internet_httpmethod
-- internet_ipv4
-- internet_ipv6
-- internet_localipv4
-- internet_macaddress
-- internet_password
-- internet_query
-- internet_safeemail
-- internet_slug
-- internet_statuscode
-- internet_statuscodemessage
-- internet_statuscodewithmessage
-- internet_tld
-- internet_url
-- internet_user
-- language_language
-- language_languageabbr
-- language_programminglanguage
-- mimetype_mimetype
-- music_genre
-- music_name
-- payment_creditcardexpirationdatestring
-- payment_creditcardnumber
-- payment_creditcardtype
-- person_firstname
-- person_firstnamefemale
-- person_firstnamemale
-- person_gender
-- person_lastname
-- person_name
-- person_namefemale
-- person_namemale
-- person_ssn
-- person_suffix
-- person_title
-- pet_cat
-- pet_dog
-- pet_name
-- phone_areacode
-- phone_e164number
-- phone_exchangecode
-- phone_number
-- phone_tollfreeareacode
-- phone_toolfreenumber
-- time_ampm
-- time_century
-- time_dayofmonth
-- time_monthname
-- time_timezone
-- time_year
-- useragent_chrome
-- useragent_firefox
-- useragent_internetexplorer
-- useragent_opera
-- useragent_safari
-- useragent_useragent
+#### Special fakers
+
+- `"null"` : set `null`
+- `""` or `"_"`: do nothing
+
+#### Others
+
+- `"address"`
+- `"address_buildingnumber"`
+- `"address_city"`
+- `"address_cityprefix"`
+- `"address_citysuffix"`
+- `"address_country"`
+- `"address_countryabbr"`
+- `"address_countrycode"`
+- `"address_latitude"`
+- `"address_longitude"`
+- `"address_postcode"`
+- `"address_secondaryaddress"`
+- `"address_state"`
+- `"address_stateabbr"`
+- `"address_streetaddress"`
+- `"address_streetname"`
+- `"address_streetsuffix"`
+- `"app_name"`
+- `"app_version"`
+- `"beer_alcohol"`
+- `"beer_blg"`
+- `"beer_hop"`
+- `"beer_ibu"`
+- `"beer_malt"`
+- `"beer_name"`
+- `"beer_style"`
+- `"blood_name"`
+- `"boolean_bool"`
+- `"car_category"`
+- `"car_fueltype"`
+- `"car_maker"`
+- `"car_model"`
+- `"car_plate"`
+- `"car_transmissiongear"`
+- `"color_css"`
+- `"color_colorname"`
+- `"color_hex"`
+- `"color_rgb"`
+- `"color_safecolorname"`
+- `"company_bs"`
+- `"company_catchphrase"`
+- `"company_ein"`
+- `"company_jobtitle"`
+- `"company_name"`
+- `"company_suffix"`
+- `"crypto_bech32address"`
+- `"crypto_bitcoinaddress"`
+- `"crypto_etheriumaddress"`
+- `"crypto_p2pkhaddress"`
+- `"crypto_p2shaddress"`
+- `"currency_code"`
+- `"currency_country"`
+- `"currency_currency"`
+- `"currency_number"`
+- `"emoji_emoji"`
+- `"emoji_emojicode"`
+- `"file_extension"`
+- `"file_filenamewithextension"`
+- `"food_fruit"`
+- `"food_vegetable"`
+- `"gamer_tag"`
+- `"gender_abbr"`
+- `"gender_name"`
+- `"genre_name"`
+- `"internet_companyemail"`
+- `"internet_domain"`
+- `"internet_email"`
+- `"internet_freeemail"`
+- `"internet_freeemaildomain"`
+- `"internet_httpmethod"`
+- `"internet_ipv4"`
+- `"internet_ipv6"`
+- `"internet_localipv4"`
+- `"internet_macaddress"`
+- `"internet_password"`
+- `"internet_query"`
+- `"internet_safeemail"`
+- `"internet_slug"`
+- `"internet_statuscode"`
+- `"internet_statuscodemessage"`
+- `"internet_statuscodewithmessage"`
+- `"internet_tld"`
+- `"internet_url"`
+- `"internet_user"`
+- `"language_language"`
+- `"language_languageabbr"`
+- `"language_programminglanguage"`
+- `"mimetype_mimetype"`
+- `"music_genre"`
+- `"music_name"`
+- `"payment_creditcardexpirationdatestring"`
+- `"payment_creditcardnumber"`
+- `"payment_creditcardtype"`
+- `"person_firstname"`
+- `"person_firstnamefemale"`
+- `"person_firstnamemale"`
+- `"person_gender"`
+- `"person_lastname"`
+- `"person_name"`
+- `"person_namefemale"`
+- `"person_namemale"`
+- `"person_ssn"`
+- `"person_suffix"`
+- `"person_title"`
+- `"pet_cat"`
+- `"pet_dog"`
+- `"pet_name"`
+- `"phone_areacode"`
+- `"phone_e164number"`
+- `"phone_exchangecode"`
+- `"phone_number"`
+- `"phone_tollfreeareacode"`
+- `"phone_toolfreenumber"`
+- `"time_ampm"`
+- `"time_century"`
+- `"time_dayofmonth"`
+- `"time_monthname"`
+- `"time_timezone"`
+- `"time_year"`
+- `"useragent_chrome"`
+- `"useragent_firefox"`
+- `"useragent_internetexplorer"`
+- `"useragent_opera"`
+- `"useragent_safari"`
+- `"useragent_useragent"`
diff --git a/app/app.go b/app/app.go
index a0ed8d6..f167eeb 100644
--- a/app/app.go
+++ b/app/app.go
@@ -65,7 +65,7 @@ func (a *App) TruncateTable(c config.SchemaConfigAction) error {
 		values := make(map[int]string)
 
 		for _, col := range c.PrimaryKey {
-			if !row[col].IsString {
+			if !row[col].IsString || row[col].IsNull {
 				value := row[col]
 				pkeys = append(pkeys, fmt.Sprintf("%s=%s", col, value.FinalValue()))
 			} else {
@@ -166,7 +166,7 @@ func (a *App) UpdateRows(c config.SchemaConfigAction, globalColumns map[string]s
 
 		for col, value := range row {
 			if value.IsUpdated && !value.IsVirtual {
-				if value.IsString {
+				if value.IsString && !value.IsNull {
 					updates = append(updates, database.GetNamedParameter(a.DbConfig.Type, col, len(values)+1))
 					values[len(values)+1] = value.FinalValue()
 				} else {
@@ -178,7 +178,7 @@ func (a *App) UpdateRows(c config.SchemaConfigAction, globalColumns map[string]s
 		for _, col := range c.PrimaryKey {
 			value := row[col]
 
-			if !value.IsString {
+			if !value.IsString || value.IsNull {
 				pkeys = append(pkeys, fmt.Sprintf("%s=%s", col, value.FinalValue()))
 			} else {
 				pkeys = append(pkeys, database.GetNamedParameter(a.DbConfig.Type, col, len(values)+1))
diff --git a/data/data.go b/data/data.go
index d48891b..cbbd954 100644
--- a/data/data.go
+++ b/data/data.go
@@ -17,7 +17,7 @@ type Data struct {
 	IsPrimaryKey bool
 	IsUpdated    bool
 
-	IsInteger bool
+	IsNumber  bool
 	IsBoolean bool
 	IsString  bool
 	IsNull    bool
@@ -70,6 +70,14 @@ func (d *Data) Update(row map[string]Data, manager faker.FakeManager) {
 		return
 	}
 
+	if d.Faker == "null" {
+		d.Value = ""
+		d.IsUpdated = true
+		d.IsNull = true
+
+		return
+	}
+
 	if d.IsTwigExpression() {
 		env := twig.New(nil)
 		params := map[string]stick.Value{}
@@ -85,6 +93,7 @@ func (d *Data) Update(row map[string]Data, manager faker.FakeManager) {
 
 		d.Value = buf.String()
 		d.IsUpdated = true
+		d.IsNull = d.Value == ""
 
 		return
 	}
diff --git a/database/database.go b/database/database.go
index d97eb1c..9998c6a 100644
--- a/database/database.go
+++ b/database/database.go
@@ -23,6 +23,23 @@ func GetNamedParameter(dbType, col string, number int) string {
 	return fmt.Sprintf("%s=$%d", col, number)
 }
 
+func IsPgNumberType(value string) bool {
+	switch value {
+	case
+		"smallint",
+		"integer",
+		"bigint",
+		"decimal",
+		"numeric",
+		"real",
+		"double precision":
+
+		return true
+	}
+
+	return false
+}
+
 func GetRows(db *sql.DB, query, table, dbType string) map[int]map[string]data.Data {
 	rows, err := db.Query(query)
 	defer rows.Close()
@@ -69,9 +86,9 @@ func GetRows(db *sql.DB, query, table, dbType string) map[int]map[string]data.Da
 
 					dataType := columnsTypes[col]
 
-					d.IsInteger = dataType == "integer"
+					d.IsNumber = IsPgNumberType(dataType)
 					d.IsBoolean = dataType == "boolean"
-					d.IsString = !d.IsBoolean && !d.IsInteger
+					d.IsString = !d.IsBoolean && !d.IsNumber
 				} else {
 					d.IsString = true
 				}
diff --git a/faker/faker.go b/faker/faker.go
index 87dbffa..2bd84b0 100644
--- a/faker/faker.go
+++ b/faker/faker.go
@@ -154,7 +154,7 @@ func NewFakeManager() FakeManager {
 }
 
 func (f *FakeManager) IsValidFaker(name string) bool {
-	if name == "" || name == "_" {
+	if name == "" || name == "_" || name == "null" {
 		return true
 	}