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SQL操作:Union (UnionBatchOp)

Java 类名:com.alibaba.alink.operator.batch.sql.UnionBatchOp

Python 类名:UnionBatchOp

功能介绍

对批式数据进行sql的UNION操作(去重)。

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

代码示例

Python 代码

from pyalink.alink import *

import pandas as pd

useLocalEnv(1)

df1 = pd.DataFrame([
    ['Ohio', 2000, 1.5],
    ['Ohio', 2000, 1.5],
    ['Ohio', 2002, 3.6],
    ['Nevada', 2001, 2.4],
    ['Nevada', 2002, 2.9],
    ['Nevada', 2003, 3.2]
])
df2 = pd.DataFrame([
    ['Nevada', 2001, 2.4],
    ['Nevada', 2003, 3.2]
])

batch_data1 = BatchOperator.fromDataframe(df1, schemaStr='f1 string, f2 bigint, f3 double')
batch_data2 = BatchOperator.fromDataframe(df2, schemaStr='f1 string, f2 bigint, f3 double')

UnionBatchOp().linkFrom(batch_data1, batch_data2).print()

Java 代码

import com.alibaba.alink.operator.batch.BatchOperator;
import com.alibaba.alink.operator.batch.source.CsvSourceBatchOp;
import com.alibaba.alink.operator.batch.sql.UnionBatchOp;
import org.junit.Test;

public class UnionBatchOpTest {
    @Test
	public void testUnionBatchOp() throws Exception {
    	List <Row> df1 = Arrays.asList(
    		Row.of("Ohio", 2000, 1.5),
    		Row.of("Ohio", 2000, 1.5),
    		Row.of("Ohio", 2002, 3.6),
    		Row.of("Nevada", 2001, 2.4),
    		Row.of("Nevada", 2002, 2.9),
    		Row.of("Nevada", 2003, 3.2)
    	);
    	List <Row> df2 = Arrays.asList(
    		Row.of("Nevada", 2001, 2.4),
    		Row.of("Nevada", 2003, 3.2)
    	);
    	BatchOperator <?> data1 = new MemSourceBatchOp(df1, "f1 string, f2 int, f3 double");
    	BatchOperator <?> data2 = new MemSourceBatchOp(df2, "f1 string, f2 int, f3 double");
    	BatchOperator <?> union = new UnionBatchOp();
    	union.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 2002 3.6000