Query Data Using Fields in a JSON object
Once a database session is created, we can call session.JSONQuery() to get a JSONQuery object.
// JSONQuery provides method to execute json query on a given user database
// The query is a json string which must contain predicates under the field
// selector. The first field in the selector can be a combinational operator
// such as "$and" or "$or" followed by a list of attributes and a list of
// conditions per attributes. A query example is shown below
//
// {
// "selector": {
// "$and": { -- top level combinational operator
// "attr1": { -- a field in the json document
// "$gte": "a", -- value criteria for the field
// "$lt": "b" -- value criteria for the field
// },
// "attr2": { -- a field in the json document
// "$eq": true -- value criteria for the field
// },
// "attr3": { -- a field in the json document
// "$lt": "a2" -- a field in the json document
// }
// }
// }
// }
type JSONQuery interface {
Execute(dbName, query string) ([]*types.KVWithMetadata, error)
}
To query data, we need to call the Execute() method of the object from above.
Pre-requisite: Create db3 with index, provide read-write permission on db3 to Alice, write sample data for queries
package main
import (
"encoding/pem"
"fmt"
"io/ioutil"
"strconv"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
"github.com/hyperledger-labs/orion-server/pkg/types"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "admin")
// if err is not nil, print and return
err = createDBWithIndex(session)
// if err is not nil, print and return
err = createAlice(session)
// if err is not nil, print and return
session, err = openSession(db, "alice")
// if err is not nil, print and return
tx, err := session.DataTx()
// if err is not nil, print and return
tx.Put("db3", "person1", []byte(`{"name":"a","age":18,"graduated":false,"rating":-234`), nil)
tx.Put("db3", "person2", []byte(`{"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}`), nil)
tx.Put("db3", "person3", []byte(`{"name":"c","age":20,"graduated":false,"rating":-4}`), nil)
tx.Put("db3", "person4", []byte(`{"name":"d","age":19,"graduated":false,"rating":-1}`), nil)
tx.Put("db3", "person5", []byte(`{"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}`), nil)
tx.Put("db3", "person6", []byte(`{"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}`), nil)
tx.Put("db3", "person7", []byte(`{"name":"g","age":28,"graduated":false,"rating":100}`), nil)
tx.Put("db3", "person8", []byte(`{"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}`), nil)
txID, receipt, err := tx.Commit(true)
// if err is not nil, print and return
fmt.Println("transaction with txID " + txID + " got committed in the block " + strconv.Itoa(int(receipt.GetHeader().GetBaseHeader().GetNumber())))
}
func createDBWithIndex(s bcdb.DBSession) error {
tx, err := s.DBsTx()
// if err is not nil, print and return
index := map[string]types.IndexAttributeType{
"name": types.IndexAttributeType_STRING,
"age": types.IndexAttributeType_NUMBER,
"graduated": types.IndexAttributeType_BOOLEAN,
"rating": types.IndexAttributeType_NUMBER,
}
err = tx.CreateDB("db3", index)
// if err is not nil, print and return
txID, receipt, err := tx.Commit(true)
// if err is not nil, print and return
fmt.Println("transaction with txID " + txID + " got committed in the block " + strconv.Itoa(int(receipt.GetHeader().GetBaseHeader().GetNumber())))
return nil
}
func createAlice(s bcdb.DBSession) error {
alicePemUserCert, err := ioutil.ReadFile("./crypto/alice/alice.pem")
// if err is not nil, print and return
aliceCertBlock, _ := pem.Decode(alicePemUserCert)
alice := &types.User{
Id: "alice",
Certificate: aliceCertBlock.Bytes,
Privilege: &types.Privilege{
DbPermission: map[string]types.Privilege_Access{
"db3": types.Privilege_ReadWrite,
},
},
}
tx, err := s.UsersTx()
// if err is not nil, print and return
err = tx.PutUser(alice, nil)
// if err is not nil, print and return
txID, receipt, err := tx.Commit(true)
// if err is not nil, print and return
fmt.Println("transaction with txID " + txID + " got committed in the block " + strconv.Itoa(int(receipt.GetHeader().GetBaseHeader().GetNumber())))
return nil
}
1) Equal operator ($eq)
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "alice")
// if err is not nil, print and return
q, err := session.JSONQuery()
// if err is not nil, print and return
queryStr := `
{
"selector": {
"graduated": {
"$eq":false
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"name": {
"$eq":"c"
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$eq":-1
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
============================
results for
{
"selector": {
"graduated": {
"$eq":false
}
}
}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
============================
results for
{
"selector": {
"name": {
"$eq":"c"
}
}
}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
============================
results for
{
"selector": {
"rating": {
"$eq":-1
}
}
}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
2) Not equal operator ($neq)
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "alice")
// if err is not nil, print and return
q, err := session.JSONQuery()
// if err is not nil, print and return
queryStr := `
{
"selector": {
"graduated": {
"$neq": [false]
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"name": {
"$neq":["a", "b", "c", "d"]
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$neq":[-1, 100, -100]
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
============================
results for
{
"selector": {
"graduated": {
"$neq": [false]
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
============================
results for
{
"selector": {
"name": {
"$neq":["a", "b", "c", "d"]
}
}
}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
============================
results for
{
"selector": {
"rating": {
"$neq":[-1, 100, -100]
}
}
}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
3) Greater than ($gt) operator
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "alice")
// if err is not nil, print and return
q, err := session.JSONQuery()
// if err is not nil, print and return
queryStr := `
{
"selector": {
"graduated": {
"$gt": false
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"name": {
"$gt":"e"
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$gt":-4
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
============================
results for
{
"selector": {
"graduated": {
"$gt": false
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
============================
results for
{
"selector": {
"name": {
"$gt":"e"
}
}
}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
============================
results for
{
"selector": {
"rating": {
"$gt":-4
}
}
}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
4) Lesser than ($lt) operator
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "alice")
// if err is not nil, print and return
q, err := session.JSONQuery()
// if err is not nil, print and return
queryStr := `
{
"selector": {
"graduated": {
"$lt": true
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"name": {
"$lt":"e"
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$lt":-4
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
============================
results for
{
"selector": {
"graduated": {
"$lt": true
}
}
}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
============================
results for
{
"selector": {
"name": {
"$lt":"e"
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
============================
results for
{
"selector": {
"rating": {
"$lt":-4
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
5) Greater than or equal ($gte) operator
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "alice")
// if err is not nil, print and return
q, err := session.JSONQuery()
// if err is not nil, print and return
queryStr := `
{
"selector": {
"graduated": {
"$gte": false
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"name": {
"$gte":"e"
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$gte":-4
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
results for
{
"selector": {
"graduated": {
"$gte": false
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
============================
results for
{
"selector": {
"name": {
"$gte":"e"
}
}
}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
============================
results for
{
"selector": {
"rating": {
"$gte":-4
}
}
}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
6) Lesser than or equal ($gte) operator
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "alice")
// if err is not nil, print and return
q, err := session.JSONQuery()
// if err is not nil, print and return
queryStr := `
{
"selector": {
"graduated": {
"$lte": true
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"name": {
"$lte":"e"
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$lte":-4
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
============================
results for
{
"selector": {
"graduated": {
"$lte": true
}
}
}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
============================
results for
{
"selector": {
"name": {
"$lte":"e"
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
============================
results for
{
"selector": {
"rating": {
"$lte":-4
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
7) Multiple logical operators ($gt, $lt, $gte, $lte,$neq)
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
// if err is not nil, print and return
session, err := openSession(db, "alice")
// if err is not nil, print and return
q, err := session.JSONQuery()
// if err is not nil, print and return
queryStr := `
{
"selector": {
"name": {
"$gt": "e",
"$lte":"h"
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$gt":-100,
"$lt":100
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
queryStr = `
{
"selector": {
"rating": {
"$gte":-100,
"$lte":100,
"$neq": [-1, 0, 12]
}
}
}
`
err = executeAndPrint(q, queryStr)
// if err is not nil, print and return
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
============================
results for
{
"selector": {
"name": {
"$gt": "e",
"$lte":"h"
}
}
}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
============================
results for
{
"selector": {
"rating": {
"$gt":-100,
"$lt":100
}
}
}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
============================
results for
{
"selector": {
"rating": {
"$gte":-100,
"$lte":100,
"$neq": [-1, 0, 12]
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
8) Combinational operators - $and and $or
package main
import (
"fmt"
"github.com/hyperledger-labs/orion-sdk-go/pkg/bcdb"
)
func main() {
db, err := createConnection()
if err != nil {
fmt.Errorf(err.Error())
return
}
session, err := openSession(db, "alice")
if err != nil {
fmt.Errorf(err.Error())
return
}
q, err := session.JSONQuery()
if err != nil {
fmt.Println(err.Error())
return
}
queryStr := `
{
"selector": {
"$and": {
"name": {
"$gt": "e",
"$lte":"h"
},
"graduated": {
"$eq": false
},
"rating": {
"$gt": -100,
"$neq": [0]
}
}
}
}
`
err = executeAndPrint(q, queryStr)
if err != nil {
fmt.Println(err.Error())
return
}
queryStr = `
{
"selector": {
"$and": {
"name": {
"$gte": "a",
"$neq": ["d", "e"],
"$lte":"h"
},
"graduated": {
"$eq": true
},
"rating": {
"$gte": -1000,
"$neq": [0],
"$lte": 1000
}
}
}
}
`
err = executeAndPrint(q, queryStr)
if err != nil {
fmt.Println(err.Error())
return
}
queryStr = `
{
"selector": {
"$or": {
"name": {
"$gt": "e",
"$lte":"h"
},
"graduated": {
"$eq": false
},
"rating": {
"$gt": -100,
"$neq": [0]
}
}
}
}
`
err = executeAndPrint(q, queryStr)
if err != nil {
fmt.Println(err.Error())
return
}
queryStr = `
{
"selector": {
"$or": {
"name": {
"$gte": "a",
"$neq": ["d", "e"],
"$lte":"h"
},
"graduated": {
"$eq": true
},
"rating": {
"$gte": -1000,
"$neq": [0],
"$lte": 1000
}
}
}
}
`
err = executeAndPrint(q, queryStr)
if err != nil {
fmt.Println(err.Error())
return
}
}
func executeAndPrint(q bcdb.JSONQuery, queryStr string) error {
kvs, err := q.Execute("db3", queryStr)
if err != nil {
return err
}
fmt.Println("============================")
fmt.Println("results for " + queryStr)
for _, kv := range kvs {
fmt.Println(kv.Key + ": " + string(kv.Value))
}
return nil
}
Output
============================
results for
{
"selector": {
"$and": {
"name": {
"$gt": "e",
"$lte":"h"
},
"graduated": {
"$eq": false
},
"rating": {
"$gt": -100,
"$neq": [0]
}
}
}
}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
============================
results for
{
"selector": {
"$and": {
"name": {
"$gte": "a",
"$neq": ["d", "e"],
"$lte":"h"
},
"graduated": {
"$eq": true
},
"rating": {
"$gte": -1000,
"$neq": [0],
"$lte": 1000
}
}
}
}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
============================
results for
{
"selector": {
"$or": {
"name": {
"$gt": "e",
"$lte":"h"
},
"graduated": {
"$eq": false
},
"rating": {
"$gt": -100,
"$neq": [0]
}
}
}
}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
============================
results for
{
"selector": {
"$or": {
"name": {
"$gte": "a",
"$neq": ["d", "e"],
"$lte":"h"
},
"graduated": {
"$eq": true
},
"rating": {
"$gte": -1000,
"$neq": [0],
"$lte": 1000
}
}
}
}
person7: {"name":"g","age":28,"graduated":false,"rating":100}
person2: {"name":"b","age":48,"graduated":true,"rating":-100,"degree":"bachelor"}
person3: {"name":"c","age":20,"graduated":false,"rating":-4}
person4: {"name":"d","age":19,"graduated":false,"rating":-1}
person6: {"name":"f","age":24,"graduated":true,"rating":12,"degree":"bachelor"}
person8: {"name":"h","age":38,"graduated":true,"rating":1230,"degree":"master"}
person5: {"name":"e","age":31,"graduated":true,"rating":0,"degree":"master"}