2016-12-31 47 views
2

我们知道在提取文件时U-SQL支持目录和文件名模式匹配。我想知道它是否支持基于ADLS中文件创建日期的模式匹配(无需实现自定义提取器)。U-SQL是否支持根据ADLS中的创建日期提取文件

说一个文件夹包含跨月创建的文件(文件名没有日期作为文件名的一部分),是否有办法只拉一个月的文件。

回答

1

U-SQL EXTRACT操作符不知道有关文件的任何元数据(如创建日期) - 只有文件名。

1

您可以使用.NET SDK构建解决方案。对于相当简单的事情,您可以使用PowerShell创建一个文件,其中将包含符合日期时间标准的所有文件。然后根据需要消费内容。

# Log in to your Azure account 
Login-AzureRmAccount 

# Modify variables as required 
$DataLakeStoreAccount = "<yourDataLakeStoreAccountNameHere>"; 
$DataLakeAnalyticsAccount = <yourDataLakeAnalyticsAccountNameHere>"; 
$DataLakeStorePath = "/Samples/Data/AmbulanceData/"; #modify as desired 
$outputFile = "Samples/Outputs/ReferenceGuide/filteredFiles.csv"; #modify as desired 
$filterDate = "2016-11-22"; 
$jobName = "GetFiles"; 

# Query directory and build main body of script. Note, there is a csv filter. 
[string]$body = 
"@initial = 
    SELECT * FROM 
    (VALUES 
" + 
(Get-AzureRmDataLakeStoreChildItem -Account $DataLakeStoreAccount -Path $DataLakeStorePath | 
Where {$_.Name -like "*.csv" -and $_.Type -eq "FILE"} | foreach { 
"(""" + $DataLakeStorePath + $_.Name + """, (DateTime)FILE.CREATED(""" + $DataLakeStorePath + $_.Name + """)), `r`n" }); 

# formattig, add column names 
$body = 
$body.Substring(0,$body.Length-4) + " 
    ) AS T(fileName, createDate);"; 

# U-SQL query and OUTPUT statement 
[string]$output = 
" 

// filter results based on desired time frame 
@filtered = 
    SELECT fileName 
    FROM @initial 
    WHERE createDate.ToString(""yyyy-MM-dd"") == ""$filterDate""; 

OUTPUT @filtered 
TO ""$outputFile"" 
USING Outputters.Csv();"; 

# bring it all together 
$script = $body + $output; 

#Execute job 
$jobInfo = Submit-AzureRmDataLakeAnalyticsJob -Account $DataLakeAnalyticsAccount -Name $jobName -Script $script -DegreeOfParallelism 1 

#check job progress 
Get-AzureRmDataLakeAnalyticsJob -Account $DataLakeAnalyticsAccount -JobId $jobInfo.JobId -ErrorAction SilentlyContinue; 

Write-Host "You now have a list of desired files to check @ " $outputFile