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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
/*
* Content before git sha 34fdeebefcbf183ed7f916f931aa0586fdaa1b40
* Copyright (c) 2016, The Gocql authors,
* provided under the BSD-3-Clause License.
* See the NOTICE file distributed with this work for additional information.
*/
package gocql_test
import (
"context"
"fmt"
"log"
gocql "github.com/gocql/gocql"
)
type MyUDT struct {
FieldA string `cql:"field_a"`
FieldB int32 `cql:"field_b"`
}
// Example_userDefinedTypesStruct demonstrates how to work with user-defined types as structs.
// See also examples for UDTMarshaler and UDTUnmarshaler if you need more control/better performance.
func Example_userDefinedTypesStruct() {
/* The example assumes the following CQL was used to setup the keyspace:
create keyspace example with replication = { 'class' : 'SimpleStrategy', 'replication_factor' : 1 };
create type example.my_udt (field_a text, field_b int);
create table example.my_udt_table(pk int, value frozen<my_udt>, PRIMARY KEY(pk));
*/
cluster := gocql.NewCluster("localhost:9042")
cluster.Keyspace = "example"
cluster.ProtoVersion = 4
session, err := cluster.CreateSession()
if err != nil {
log.Fatal(err)
}
defer session.Close()
ctx := context.Background()
value := MyUDT{
FieldA: "a value",
FieldB: 42,
}
err = session.Query("INSERT INTO example.my_udt_table (pk, value) VALUES (?, ?)",
1, value).WithContext(ctx).Exec()
if err != nil {
log.Fatal(err)
}
var readValue MyUDT
err = session.Query("SELECT value FROM example.my_udt_table WHERE pk = 1").WithContext(ctx).Scan(&readValue)
if err != nil {
log.Fatal(err)
}
fmt.Println(readValue.FieldA)
fmt.Println(readValue.FieldB)
// a value
// 42
}
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