get df column as list code example

Example 1: how to get a dataframe column as a list

import pandas as pd

data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
             'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}

df = pd.DataFrame(data_dict)

print(f"DataFrame:\n{df}\n")
print(f"column types:\n{df.dtypes}")

col_one_list = df['one'].tolist()

col_one_arr = df['one'].to_numpy()

print(f"\ncol_one_list:\n{col_one_list}\ntype:{type(col_one_list)}")
print(f"\ncol_one_arr:\n{col_one_arr}\ntype:{type(col_one_arr)}")

Example 2: get column names as list

public static List<String> getColumnNames(){


        List<String> columnList = new ArrayList<>();
        try {
            ResultSetMetaData rsMetaData = rs.getMetaData();
            for (int colNum = 1; colNum < getColumnCount()  ; colNum++) {
                columnList.add(rsMetaData.getColumnLabel(colNum));
            }
        } catch (SQLException e) {
       System.out.println("ERROR WHILE GETTING COLUMN NAMES "+ e.getMessage());
        }

        return columnList;
    }