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How to extract data from Excel (specific columns) using SQL or PL/SQL or Python

I was wondering if someone could help me understand how I could use Sql or Pl/Sql or python, or any convenient scripting language, to cherry pick specific data values (just a few columns on the excel sheet).
Any inputs would be highly appreciated!
Thanks!!

In Java, you can use Apache POI for that.
https://poi.apache.org
Example:
// Creating a Workbook from an Excel file (.xls or .xlsx)
Workbook workbook = WorkbookFactory.create(new File("my_file.xlsx"));
// Getting the Sheet at index zero
Sheet sheet = workbook.getSheetAt(0);
Iterator<Row> rowIterator = sheet.rowIterator();
while (rowIterator.hasNext()) {
Row row = rowIterator.next();
// Now let's iterate over the columns of the current row
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
System.out.print(cell.getStringCellValue() + "\t");
}
System.out.println();
}

In Python, you can use Pandas to drop the columns you do not want or you can keep the ones you do want. I suppose whichever list is smaller.
import pandas as pd
df = pd.read_csv('filename.csv')
#Drop Columns Not Needed
df = df.drop(['ColumnName1','ColumnName2'], axis=1)
#Keep Columns Needed
df = df[['ColumnName3','ColumnName4']]

Set Cellstyle of a org.apache.poi.ss.usermodel.Cell to boolean

I would like to write a boolean-value into an excel-cell, but instead of setting the cellStyle to "logic" the cellStyle will become "number" instead.
private void writeToDocument(XSSFWorkbook workbook) {
Sheet sheet = workbook.createSheet("testSheet");
Row row = sheet.createRow(0);
Cell cell = row.createCell(0);
cell.setCellValue(true);
}
I already tryied
CellStyle cellStyle = workbook.createCellStyle();
cellStyle.setDataFormat([short s]);
cell.setCellStyle(cellStyle);
but no short s between 0 and 49 did the job.

When appropriate overloaded version of setCellValue is used the cell types will be assigned automatically, for example
cell.setCellValue(true);
System.out.println(cell.getCellType());
prints BOOLEAN
Checked on org.apache.poi:poi:4.1.1

You can use the following:
Row row = sheet.createRow(lineNumber);
Cell cell = row.createCell(1, CellType.BOOLEAN);
This will create a cell styled to persist boolean.

Use below code for Boolean value
private void writeToDocument(XSSFWorkbook workbook) {
Sheet sheet = workbook.createSheet("testSheet");
Row row = sheet.createRow(0);
Cell cell = row.createCell(0);
cell.setCellType(HSSFCell.CELL_TYPE_BOOLEAN);
cell.setCellValue((Boolean) true);
}

This is how to customize a date, potentially you may try it with boolean
final XSSFCellStyle date = sheet.getWorkbook().createCellStyle();
date.setDataFormat(
sheet.getWorkbook()
.getCreationHelper()
.createDataFormat()
.getFormat(pattern)
);
cell = row.createCell(index);
cell.setCellStyle(date);

I am getting Null Pointer Exception when Accessing the Cell Which has the Value?

I am using the Apache POI Library to get the data from EXCEL Sheet. I have attached the EXCEL Sheet which has the yellow part highlighted. I am trying to extract the all the data from EXCEL Sheet but I am not getting the data from the highlighted part. It gives the null pointer exception when trying to access these cells.
SAMPLE Document :
Document
SAMPLE Code.
FileInputStream inputStream = new FileInputStream(file);
Workbook workbook = new XSSFWorkbook(inputStream);
Sheet firstSheet = workbook.getSheetAt(0);
Iterator<Row> iterator = firstSheet.iterator();
while (iterator.hasNext()) {
Row nextRow = iterator.next();
Iterator<Cell> cellIterator = nextRow.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
System.out.print(cell.getStringCellValue());
System.out.print(",");
}
System.out.println();
}
workbook.close();
inputStream.close();
When you run the above program you will get some fields are not extracted from the excel sheet(Highlighted Part). When you explicitly try to access those cells you will get the null pointer exception.

Cannot reproduce the behavior. If System.out.print(cell.getStringCellValue()); throws a NPE, then cell must be null. But cell cannot be null according to your code since the Row.cellIterator iterates over cells only which are present and not null.
Have downloaded your SAMPLE.xlsx and used the code from Busy Developers' Guide - Getting the cell contents. This code reads all cells without problems.
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.*;
import java.io.FileInputStream;
class ReadExcelExampleDataFormatter {
public static void main(String[] args) throws Exception {
Workbook wb = WorkbookFactory.create(new FileInputStream("SAMPLE.xlsx"));
DataFormatter formatter = new DataFormatter();
FormulaEvaluator evaluator = wb.getCreationHelper().createFormulaEvaluator();
Sheet sheet = wb.getSheetAt(0);
for (Row row : sheet) {
for (Cell cell : row) {
CellReference cellRef = new CellReference(row.getRowNum(), cell.getColumnIndex());
System.out.print(cellRef.formatAsString());
System.out.print(" - ");
// get the text that appears in the cell by getting the cell value and applying any data formats (Date, 0.00, 1.23e9, $1.23, etc)
String text = formatter.formatCellValue(cell);
System.out.println(text);
}
}
wb.close();
}
}
Part of the result (your first yellow range):
A15 - Report
Summary
B15 - Real Estate
C15 - Count
D15 - 3
E15 - 0
F15 - 2
A16 -
B16 -
C16 - Balance
D16 - $94,263.00
E16 - $0.00
F16 - $94,263.00
A17 -
B17 -
C17 - Current
D17 - 2
E17 - 0
F17 - 2
A18 -
B18 -
C18 - Delinquent
D18 - 0
E18 - 0
F18 - 0

Apache POI formatting double numbers in Excel files

I am using apache-poi for creating some reports. I have an issue with the decimal separator. Right now I have the following displayed in the excel file:
For 111.2343 -> 111.23
For 111.23 -> 111.23
For 111.2 -> 111.2
For 111 -> 111. (see the dot at the end)
The problem is with 111 number. I don't want to see the trailing dot (or comma, depending on language).
Here is my current code to format the cells. Can this be achieved using apache-poi?
Thank you,
Iulian
PS: Is there a way to use java.text.Format in poi? I see this has DecimalFormat setDecimalSeparatorAlwaysShown method which does what I want.
private void createColumnStyle(XSSFSheet sheet, int maxRows,int col)
{
XSSFWorkbook wb = sheet.getWorkbook();
XSSFFont font = wb.createFont();
font.setFontHeightInPoints((short)10);
font.setFontName("Calibri");
XSSFCellStyle colStyle = wb.createCellStyle();
colStyle.setFont(font);
colStyle.setAlignment(HorizontalAlignment.RIGHT);
colStyle.setBorderBottom(XSSFCellStyle.BORDER_THIN);
colStyle.setBorderTop(XSSFCellStyle.BORDER_THIN);
colStyle.setBorderRight(XSSFCellStyle.BORDER_THIN);
colStyle.setBorderLeft(XSSFCellStyle.BORDER_THIN);
CreationHelper createHelper = wb.getCreationHelper();
colStyle.setDataFormat(createHelper.createDataFormat().getFormat("#,##0.##"));
for (int i=3; i<maxRows; i++ )
{
XSSFCell cell = sheet.getRow(i).createCell(col);
cell.setCellStyle(colStyle);
}
}

Using DecimalFormat works fine for all the cases:
DecimalFormat dec = new DecimalFormat("#.00");
double cellValue = Double.valueOf(dec.format(111));
XSSFCell cell = sheet.createRow(0).createCell(0);
cell.setCellValue(cellValue);
this set the cell value to 111 only.

Get cell value from Excel file based on the column name in JAVA

I am trying to read an Excel file and get the value of a particular column.
I used row.getCell(0),toString() to get the first column value. Instead of using the column index, I wanted to use the Column Name. How can I do this ? getCell allows only the index to be entered. how can I pass the column name. Something like row.getCell(COLUMN_NAME)

Looks like you are utilizing apache-poi for your purpose. You can use a util class CellReference, sample usage below:
XSSFSheet ws = wb.getSheet("Sheet1");
CellReference cellReference = new CellReference("A11");
XSSFRow row = sheet.getRow(cellReference.getRow());
if (row != null) {
XSSFCell cell = row.getCell(cellReference.getCol());
}