SQL操作：Minus (MinusBatchOp)

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

Python 类名：MinusBatchOp

功能介绍

对批式数据进行sql的MINUS操作。(一个数据集减去另一个数据集, 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')

MinusBatchOp().linkFrom(batch_data1, batch_data2).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.MinusBatchOp;
import org.junit.Test;

public class MinusBatchOpTest {
	@Test
	public void testMinusBatchOp() 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 <?> minusAllOp = new MinusBatchOp();
		minusAllOp.linkFrom(data1, data2).print();
	}
}

运行结果

f1	f2	f3
Nevada	2002	2.9000
Ohio	2000	1.5000
Ohio	2002	3.6000