Question

如何在不使用instr和substr的情况下从电子邮件中提取用户名。我在oracle db中工作。我试过这个

select regexp_replace(email,'^.*@') from students;

但是我输出了域名.pls帮助

Answer 1

select regexp_replace(email,'@.*$') from students

它取代了从@开始直到行尾的所有内容。

Answer 2

试试这个

$ComputerNameArray = Get-Content -Path c:\restarted.txt
[int]$SleepTimer = "1" #minutes to attempt after
[int]$Attempts = "2"
$DefaultBackgroundColor = (Get-Host).ui.rawui.BackgroundColor

foreach($ComputerName in $ComputerNameArray) {
    $AttemptsCounter = 0
    $RemainingAttempts = $Attempts - $AttemptsCounter

    Write-Host "Testing to see if ""$ComputerName"" is coming online..." -BackgroundColor $DefaultBackgroundColor

    while($RemainingAttempts -gt 0) {
        if(Test-Connection -ComputerName $ComputerName -Quiet -Count 1) {
            Write-Host """$ComputerName""" -BackgroundColor Green  -NoNewline
            Write-Host " Is coming online...Skipping to offline one's"
            break
        } else {
            Write-Host """$ComputerName""" -BackgroundColor Red  -NoNewline
            Write-Host " is Offline" -BackgroundColor Red -ForegroundColor Black -NoNewline
            Write-Host ". Pausing for $SleepTimer minutes. Remaining attempts: $($RemainingAttempts - 1)"
            Start-Sleep -Seconds ($SleepTimer * 60)
            $RemainingAttempts--
        }
    }

    if($RemainingAttempts -eq 0) {
        Write-Host "Maximum number of attempts reached" -BackgroundColor $DefaultBackgroundColor
    }
}

请注意，此查询假定您的用户名中只包含字符（即@符号前面的字符）并且它是leng

如果您的用户名包含字符和数字的组合，则可以尝试以下代码

select regexp_substr(email, '[A-Z]{1,10}') REG_EXP from students;

注意：如果您使用小写字母，则此脚本可以使用，如果您的用户名超过10个字符，请相应更改{1,10}部分代码

从电子邮件中提取名称而不使用substr和instr

2 个答案: