# Update a specific cells in existing table
Sometimes, you may need to retain the content of an existing table while modifying specific cells. To achieve this, use the keyword `null` to skip the cells you don't want to change.
In the example below, we updated the cell value in row 2, column 3 from `70%` to `NA`, and added a new row with data for `FIAT`. All other cells remain unchanged.
Before vs after
Template Presentation
{% file src="/files/r0OFgbqkhyXkgtbjEuAi" %}
JSON Payload
```json
{
"presentation": {
"template": "Table-Shape-New-Data.pptx",
"export_version": "Pptx2013",
"slides": [
{
"type": "slide",
"slide_index": 0,
"shapes": [
{
"name": "Mytable",
"data_cells": [
[
null,
null,
null,
null
],
[
null,
null,
"NA",
null
],
[
null,
null,
null,
null
],
[
null,
null,
null,
null
],
[
"FIAT",
"30%",
"40%",
"50%"
]
]
}
]
}
]
}
}
```
---
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