Every click, React wants to add a div, to the array. Why can't it be rendered?

import React, { Component } from "react";

export default class Scroll extends React.Component {
  constructor(props) {
    super(props)
    this.state = {
      row: [],
      num: 0,
    }
  }

  addRow = () => {
    const { row } = this.state;
    row.push(<div key={row.length + 1}>{row.length + 1}</div>);
    this.setState({
      row,
    })
  }

  render() {
    const { row, num } = this.state;
    return (
      <div>

        <div>
          <button onClick={this.addRow}></button>
          {num}
        </div>
      </div>

    )
  }
}
Jul.09,2021
Traverse row when

render

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b44472-2bf52.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b44472-2bf52.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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