Java 类名:com.alibaba.alink.operator.batch.sql.FullOuterJoinBatchOp
Python 类名:FullOuterJoinBatchOp
功能介绍
对批式数据进行sql的FULL OUTER JOIN操作。
参数说明
| 名称 | 中文名称 | 描述 | 类型 | 是否必须? | 取值范围 | 默认值 | | —- | —- | —- | —- | —- | —- | —- |
| joinPredicate | where语句 | where语句 | String | ✓ | | |
| selectClause | select语句 | select语句 | String | ✓ | | |
| type | join类型 | join类型: “join”, “leftOuterJoin”, “rightOuterJoin” 或 “fullOuterJoin” | String | | “JOIN”, “LEFTOUTERJOIN”, “RIGHTOUTERJOIN”, “FULLOUTERJOIN” | “JOIN” |
代码示例
Python 代码
from pyalink.alink import *
import pandas as pd
useLocalEnv(1)
df = pd.DataFrame([
['Ohio', 2000, 1.5],
['Ohio', 2001, 1.7],
['Ohio', 2002, 3.6],
['Nevada', 2001, 2.4],
['Nevada', 2002, 2.9],
['Nevada', 2003, 3.2]
])
batch_data1 = BatchOperator.fromDataframe(df, schemaStr='f1 string, f2 bigint, f3 double')
batch_data2 = BatchOperator.fromDataframe(df, schemaStr='f1 string, f2 bigint, f3 double')
op = FullOuterJoinBatchOp().setJoinPredicate("a.f1=b.f1 and a.f2=b.f2").setSelectClause("a.f1, a.f2, a.f3")
result = op.linkFrom(batch_data1, batch_data2)
result.print()
Java 代码
import com.alibaba.alink.operator.batch.BatchOperator;
import com.alibaba.alink.operator.batch.source.MemSourceBatchOp;
import com.alibaba.alink.operator.batch.sql.FullOuterJoinBatchOp;
import org.junit.Test;
public class FullOuterJoinBatchOpTest {
@Test
public void testFullOuterJoinBatchOp() throws Exception {
List <Row> df = Arrays.asList(
Row.of("Ohio", 2000, 1.5),
Row.of("Ohio", 2001, 1.7),
Row.of("Ohio", 2002, 3.6),
Row.of("Nevada", 2001, 2.4),
Row.of("Nevada", 2002, 2.9),
Row.of("Nevada", 2003, 3.2)
);
BatchOperator <?> data1 = new MemSourceBatchOp(df, "f1 string, f2 int, f3 double");
BatchOperator <?> data2 = new MemSourceBatchOp(df, "f1 string, f2 int, f3 double");
BatchOperator <?> joinOp =
new FullOuterJoinBatchOp().setJoinPredicate("a.f1=b.f1 and a.f2=b.f2").setSelectClause(
"a.f1, a.f2, a.f3");
joinOp.linkFrom(data1, data2).print();
}
}
运行结果
| f1 | f2 | f3 | | —- | —- | —- |
| Nevada | 2001 | 2.4000 |
| Nevada | 2002 | 2.9000 |
| Nevada | 2003 | 3.2000 |
| Ohio | 2000 | 1.5000 |
| Ohio | 2001 | 1.7000 |
| Ohio | 2002 | 3.6000 |