【Apache Doris】Stream Load 最佳实践指南

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发布于 2024-12-24 16:17:24

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“Doris 的导入方式比较多，一般情况下每个场景都有对应的数据导入方式，比如Streamload、HdfsLoad（逐渐替换BrokerLoad）、RoutineLoad、MySqlLoad等。其中大家用的最多的可能是StreamLoad的方式，因为一般用doris flink connector 、doris spark connector、datax等进行数据同步时，底层都是走streamload。由于 spark doris connnector/flink doris connnector/datax 底层都是走的streamload，所以遇到的导入报错情况也基本一致。本文将一起学习Doris的Stream Load最佳实践指南。

导入报错梳理实践

1. 分区没有提前创建Schema

CREATE TABLE IF NOT EXISTS tb_dynamic_partition_test2(
    `sid` LARGEINT NOT NULL COMMENT "学生id",
    `name` VARCHAR(50) NOT NULL COMMENT "学生名字",
    `class` INT COMMENT "学生所在班级",
    `age` SMALLINT COMMENT "学生年龄",
    `sex` TINYINT COMMENT "学生性别",
    `phone` LARGEINT COMMENT "学生电话",
    `address` VARCHAR(500)  NOT NULL COMMENT "学生家庭地址",
    `date` DATETIME NOT NULL COMMENT "数据录入时间"
)
ENGINE=olap
DUPLICATE KEY (`sid`,`name`)
PARTITION BY RANGE(`date`)()
DISTRIBUTED BY HASH (`sid`) BUCKETS 4
PROPERTIES
(
"dynamic_partition.enable"="true", -- 开启动态分区
"dynamic_partition.start"="-3", -- 保留前三天的分区
"dynamic_partition.end"="1", -- 往后创建一个分区
"dynamic_partition.time_unit"="DAY", -- 按天分区
"dynamic_partition.prefix"="p_", -- 分区字段以p_开始
"dynamic_partition.replication_num"="1", -- 动态分区中的副本数指定为1
"dynamic_partition.buckets"="4" -- 动态分区中的分桶数量为 4 
);

-- data:
1,lisi,1001,18,1,1008610010,beijing,2024-04-26

Streamload:

curl --location-trusted -u root -H "column_separator:,"  -T /mnt/disk2/test.csv http://ip:8030/api/test/tb_dynamic_partition_test2/_stream_load

ERROR:

curl http://ip:8040/api/_load_error_log?file=__shard_6/error_log_insert_stmt_974c58560ccd1a48-f470414c963ae092_974c58560ccd1a48_f470414c963ae092

Reason: no partition for this tuple. tuple=+---------------+---------------+----------------------+--------------------+-------------------+-----------------------+---------------+----------------+
|sid(Int128)    |name(String)   |class(Nullable(Int32))|age(Nullable(Int16))|sex(Nullable(Int8))|phone(Nullable(Int128))|address(String)|date(DateTimeV2)|
+---------------+---------------+----------------------+--------------------+-------------------+-----------------------+---------------+----------------+
|              1|           lisi|                  1001|                  18|                  1|             1008610010|        beijing|2024-04-26 00...|
+---------------+---------------+----------------------+--------------------+-------------------+-----------------------+---------------+----------------+
8 rows in block, only show first 1 rows.

处理方式，添加对应分区：

// 关闭动态分区
ALTER TABLE tb_dynamic_partition_test2 SET ("dynamic_partition.enable" = "false");
// 添加分区
ALTER TABLE test.tb_dynamic_partition_test2
ADD PARTITION p_20240426 VALUES [("2024-04-26 00:00:00"), ("2024-04-27 00:00:00")) ("replication_num"="1");
// 打开动态分区
ALTER TABLE tb_dynamic_partition_test2 SET ("dynamic_partition.enable" = "true");]

正常导入数据：

总结：

如果是数据找到不到对应分区，可以先排查分区是否创建，或者补分区、修改分区策略，保证数据在分区范围内。

2.数据和字段类型不匹配Schema

-- table schema：
CREATE TABLE IF NOT EXISTS test(
    `sid` LARGEINT NOT NULL COMMENT "学生id",
    `name` VARCHAR(5) NOT NULL COMMENT "学生名字",
    `class` INT COMMENT "学生所在班级",
    `age` SMALLINT COMMENT "学生年龄",
    `sex` TINYINT COMMENT "学生性别",
    `phone` LARGEINT COMMENT "学生电话",
    `address` VARCHAR(5)  NOT NULL COMMENT "学生家庭地址",
    `date` DATETIME NOT NULL COMMENT "数据录入时间"
)
ENGINE=olap
DUPLICATE KEY (`sid`,`name`)
DISTRIBUTED BY HASH (`sid`) BUCKETS 4
PROPERTIES
(
"replication_num"="1"
);

-- 数据：
1,lisixxxxxxxxxxxxxxxxxxxx,1001,18,1,1008610010,bj,2024-04-26

Streamload:

curl --location-trusted -u root -H "column_separator:,"  -T /mnt/disk2/liyuanyuan/data/test.csv http://10.16.10.6:18739/api/test/test/_stream_load

ERROR:

error:
curl http://10.16.10.6:18749/api/_load_error_log?file=__shard_0/error_log_insert_stmt_e743756cd8da0bf9-47820b98b0cae2b0_e743756cd8da0bf9_47820b98b0cae2b0
Reason: column_name[name], the length of input is too long than schema. first 32 bytes of input str: [lisixxxxxxxxxxxxxxxxxxxx] schema length: 5; actual length: 24; . src line [];

从报错来看，是 name 字段导入的数据长度大于字段类型的长度

处理方式,参考：：

ALTER-TABLE-COLUMN - Apache Doris-- 修改列长度

ALTER TABLE test.test MODIFY COLUMN name VARCHAR(50) KEY ;

导入成功：

3. 导入列和schema 列不对应Schema

-- table schema
CREATE TABLE IF NOT EXISTS test2(
    `sid` LARGEINT NOT NULL COMMENT "学生id",
    `name` VARCHAR(50) NOT NULL COMMENT "学生名字",
    `class` INT COMMENT "学生所在班级",
    `age` SMALLINT COMMENT "学生年龄",
    `sex` TINYINT COMMENT "学生性别",
    `phone` LARGEINT COMMENT "学生电话",
    `address` VARCHAR(50)  NOT NULL COMMENT "学生家庭地址",
    `date` DATETIME NOT NULL COMMENT "数据录入时间"
)
ENGINE=olap
DUPLICATE KEY (`sid`,`name`)
DISTRIBUTED BY HASH (`sid`) BUCKETS 4
PROPERTIES
(
"replication_num"="1"
);

--data
1,xxxxxxxxxxxxxxxxxxxxxxx,1001,18,1,1008610010,beijing,2024-04-26,test_column

Streamload:

curl --location-trusted -u root -H "column_separator:,"  -T /mnt/disk2/liyuanyuan/data/test2.csv http://10.16.10.6:18739/api/test/test2/_stream_load

ERROR:

Reason: actual column number in csv file is  more than  schema column number.actual number: 9, schema column number: 8; line delimiter: [
], column separator: [,], result values:[1, xxxxxxxxxxxxxxxxxxxxxxx, 1001, 18, 1, 1008610010, beijing, 2024-04-26, test_column, ]. src line [1,xxxxxxxxxxxxxxxxxxxxxxx,1001,18,1,1008610010,beijing,2024-04-26,test_column];

处理方式,参考：

ALTER-TABLE-COLUMN - Apache Doris-- 添加列

ALTER TABLE test.test2 ADD COLUMN new_col varchar(50) ;

导入成功：

4.csv中含有特殊字符导入失败

比如：flink/spark to doris 使用csv举例子：以下图为例子，有时候在进行数据同步的时候会遇到一些问题，比如表schema 的字段是固定的32个，但是实际列数小于schema列数，甚至有可能是变动的，这种情况一般是数据中有分隔符导致的，可以考虑换成json格式。

Flink Flink Doris Connector - Apache Doris

Spark Spark Doris Connector - Apache Doris

properties.setProperty("format", "json");
properties.setProperty("read_json_by_line", "true");

含包围符数据导入

1. 包围符数据导入

Schema:

CREATE TABLE IF NOT EXISTS test3(
    `sid` LARGEINT NOT NULL COMMENT "学生id",
    `name` VARCHAR(50) NOT NULL COMMENT "学生名字",
    `class` INT COMMENT "学生所在班级",
    `age` SMALLINT COMMENT "学生年龄",
    `sex` TINYINT COMMENT "学生性别",
    `phone` LARGEINT COMMENT "学生电话",
    `address` VARCHAR(50)  NOT NULL COMMENT "学生家庭地址",
    `date` DATETIME NOT NULL COMMENT "数据录入时间"
)
ENGINE=olap
DUPLICATE KEY (`sid`,`name`)
DISTRIBUTED BY HASH (`sid`) BUCKETS 4
PROPERTIES
(
"replication_num"="1"
);

--data
"1","xxxxxxx","1001","18","1","1008610010","beijing","2024-04-26"

Streamload:

curl --location-trusted -u root -H "column_separator:,"  -H "enclose:\"" -H "trim_double_quotes:true"  -T /mnt/disk2/liyuanyuan/data/test3.csv http://10.16.10.6:18739/api/test/test3/_stream_load

参考Streamload Stream Load - Apache Doris：

enclose：指定包围符。
trim_double_quotes：为 true 时裁剪掉 CSV 文件每个字段最外层的双引号。

处理方式：

2. 部分数据有包围符

Schema:

CREATE TABLE IF NOT EXISTS test4(
    `sid` LARGEINT NOT NULL COMMENT "学生id",
    `name` VARCHAR(50) NOT NULL COMMENT "学生名字",
    `class` INT COMMENT "学生所在班级",
    `age` SMALLINT COMMENT "学生年龄",
    `sex` TINYINT COMMENT "学生性别",
    `phone` LARGEINT COMMENT "学生电话",
    `address` VARCHAR(50)  NOT NULL COMMENT "学生家庭地址",
    `date` DATETIME NOT NULL COMMENT "数据录入时间"
)
ENGINE=olap
DUPLICATE KEY (`sid`,`name`)
DISTRIBUTED BY HASH (`sid`) BUCKETS 4
PROPERTIES
(
"replication_num"="1"
);

--data 部分数据有包围符，包围符中的数据有和列分隔符相同的分隔符
"1","xx,x,x,xxx",1001,18,"1",1008610010,"bei,jing",2024-04-26

Streamload:

curl --location-trusted -u root -H "column_separator:,"  -H "enclose:\"" -H "trim_double_quotes:true"  -T /mnt/disk2/liyuanyuan/data/test4.csv http://10.16.10.6:18739/api/test/test4/_stream_load

处理方式参考：Streamload Stream Load - Apache Doris：

enclose：指定包围符。
trim_double_quotes：为 true 时裁剪掉 CSV 文件每个字段最外层的双引号。

列名含有特殊字符

Schema:

CREATE TABLE loadtest
(
    `@col` DATETIME NOT NULL COMMENT "时间",
    `colint` INT NOT NULL COMMENT "int",
    `colvar` INT COMMENT "字符串"
)
DUPLICATE KEY(`@col`, `colint`)
DISTRIBUTED BY HASH(`@col`) BUCKETS 1
PROPERTIES (
"replication_allocation" = "tag.location.default: 1");data：2024-05-14 20:00:00,1,1

Streamload:

curl --location-trusted -u "root:" -T bb -H "format:csv" -H "column_separator:,"  -H 'columns:`@col`,colint,colvar' http://10.16.10.x:18739/api/test/loadtest/_stream_load

说明：

需要将 -H "columns:@coltime,colint,colvar" 改成单引号 + 反引号就可以，因为双引号 curl 会转译

Windows 换行符问题

如果导入windows 数据后查询有问题，出现类似 select * from table where col = "xxx" 查不到数据，但实际上 col字段 xxx 数据是存在的，这种情况就要考虑是否是因为最后一列多出了 \r 。

排查方式：

od -c test_data.csv 查看是否有\r\n 存在

处理方式：

导入数据时候指定换行符为 \r\n：-H "line_delimiter:\r\n"

Streamload 表达式写法

Demo 1：

Schema:

CREATE TABLE test.test_streamload(
    user_id            BIGINT       NOT NULL COMMENT "用户 ID",
    name               VARCHAR(20)           COMMENT "用户姓名",
    age                INT                   COMMENT "用户年龄"
)
DUPLICATE KEY(user_id)
DISTRIBUTED BY HASH(user_id) BUCKETS 10
properties (
"replication_allocation" = "tag.location.default: 1"
);

-- data：1,xxx,18

Streamload:

curl --location-trusted -u "root:" -T aa -H "format:csv" -H "column_separator:," -H "columns:user_id,tmp,age,name=upper(tmp)" http://10.16.10.6:18739/api/test/loadtest/_stream_load

Demo2 ：

Schema:

CREATE TABLE test.test_streamload2(
    c1            INT,
    c2               INT,
    c3               VARCHAR(20)
)
DUPLICATE KEY(c1)
DISTRIBUTED BY HASH(c1) BUCKETS 10
properties (
"replication_allocation" = "tag.location.default: 1"
);

-- data：1,2,ab,cd,ef

Streamload:

curl --location-trusted -u "root:" -T aa -H "format:csv" -H "column_separator:," -H "columns:c1,c2,A,B,C,c3=CONCAT(A,B,C)" http://127.0.0.1:8030/api/test/test_streamload2/_stream_load