# 使用分区投影在 Athena 中为 CloudTrail 日志创建表
<a name="create-cloudtrail-table-partition-projection"></a>

由于 CloudTrail 日志具有一个已知结构，您可以预先指定该结构的分区方案，因此可以使用 Athena 分区投影功能减少查询运行时间并自动管理分区。当添加新数据时，分区投影会自动添加新分区。这样就不必使用 `ALTER TABLE ADD PARTITION` 手动添加分区了。

以下示例 `CREATE TABLE` 语句会自动在 CloudTrail 日志上从指定日期开始到当前为单个 AWS 区域 使用分区投影。在 `LOCATION` 和 `storage.location.template` 子句中，将*存储桶*、*account-id* 和 *aws-region* 占位符替换为对应的相同值。对于 `projection.timestamp.range`，将 *2020*/*01*/*01* 替换为要使用的开始日期。成功运行查询后，您可以查询表。您无需运行 `ALTER TABLE ADD PARTITION` 来加载分区。

```
CREATE EXTERNAL TABLE cloudtrail_logs_pp(
    eventversion STRING,
    useridentity STRUCT<
        type: STRING,
        principalid: STRING,
        arn: STRING,
        accountid: STRING,
        invokedby: STRING,
        accesskeyid: STRING,
        username: STRING,
        onbehalfof: STRUCT<
             userid: STRING,
             identitystorearn: STRING>,
        sessioncontext: STRUCT<
            attributes: STRUCT<
                mfaauthenticated: STRING,
                creationdate: STRING>,
            sessionissuer: STRUCT<
                type: STRING,
                principalid: STRING,
                arn: STRING,
                accountid: STRING,
                username: STRING>,
            ec2roledelivery:string,
            webidfederationdata: STRUCT<
                federatedprovider: STRING,
                attributes: map<string,string>>
        >
    >,
    eventtime STRING,
    eventsource STRING,
    eventname STRING,
    awsregion STRING,
    sourceipaddress STRING,
    useragent STRING,
    errorcode STRING,
    errormessage STRING,
    requestparameters STRING,
    responseelements STRING,
    additionaleventdata STRING,
    requestid STRING,
    eventid STRING,
    readonly STRING,
    resources ARRAY<STRUCT<
        arn: STRING,
        accountid: STRING,
        type: STRING>>,
    eventtype STRING,
    apiversion STRING,
    recipientaccountid STRING,
    serviceeventdetails STRING,
    sharedeventid STRING,
    vpcendpointid STRING,
    vpcendpointaccountid STRING,
    eventcategory STRING,
    addendum STRUCT<
      reason:STRING,
      updatedfields:STRING,
      originalrequestid:STRING,
      originaleventid:STRING>,
    sessioncredentialfromconsole STRING,
    edgedevicedetails STRING,
    tlsdetails STRUCT<
      tlsversion:STRING,
      ciphersuite:STRING,
      clientprovidedhostheader:STRING>
  )
PARTITIONED BY (
   `timestamp` string)
ROW FORMAT SERDE 'org.apache.hive.hcatalog.data.JsonSerDe'
STORED AS INPUTFORMAT 'com.amazon.emr.cloudtrail.CloudTrailInputFormat'
OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
LOCATION
  's3://amzn-s3-demo-bucket/AWSLogs/account-id/CloudTrail/aws-region'
TBLPROPERTIES (
  'projection.enabled'='true', 
  'projection.timestamp.format'='yyyy/MM/dd', 
  'projection.timestamp.interval'='1', 
  'projection.timestamp.interval.unit'='DAYS', 
  'projection.timestamp.range'='2020/01/01,NOW', 
  'projection.timestamp.type'='date', 
  'storage.location.template'='s3://amzn-s3-demo-bucket/AWSLogs/account-id/CloudTrail/aws-region/${timestamp}')
```

更多有关分区投影的信息，请参阅 [将分区投影与 Amazon Athena 结合使用](partition-projection.md)。