This error will also occur following error PRJ0007: Could not create output directory 'directory'. Error PRJ0007 means that the $(IntDir) directory could not be created, implying the creation of temporarily files will also fail.
ie could not create temporary file for processing
Snowflake supports creating temporary tables for storing non-permanent, transitory data (e.g. ETL data, session-specific data). Temporary tablesonly exist within the session in which they were created and persist only for the remainder of the session. As such, they are not visible to otherusers or sessions. Once the session ends, data stored in the table is purged completely from the system and, therefore, is not recoverable, eitherby the user who created the table or Snowflake.
For the duration of the existence of a temporary table, the data stored in the table contributes to the overall storage charges that Snowflake billsyour account. To prevent any unexpected storage changes, particularly if you create large temporary tables in sessions that you maintain for periodslonger than 24 hours, Snowflake recommends explicitly dropping these tables once they are no longer needed. You can also explicitly exit the sessionin which the table was created to ensure no additional charges are accrued.
Temporary tables can have a Time Travel retention period of 1 day; however, a temporary table is purged once the session (in which the tablewas created) ends so the actual retention period is for 24 hours or the remainder of the session, whichever is shorter.
I'm using the mclapply function in the multicore package to do parallel processing. It seems that all child processes started produce the same names for temporary files given by the tempfile function. i.e. if I have four processors,
will give four exactly same filenames. Obviously I need the temporary files to be different so that the child processes don't overwrite each others' files. When using tempfile indirectly, i.e. calling some function that calls tempfile I have no control over the filename.
Background: When you open attachments on email directly from Outlook, a copy is written to a temporary folder on your hard drive so your the virus scanner can check it before it is opened. The folder Outlook writes this temp file to is under the Temporary Internet Files folder where IE writes pages to when you surf the internet. This offers more security as only your user account and the computer administrator account can view the files under this folder. The only way to avoid "losing" attachments in this well hidden folder is to save them to your hard drive, before opening. Few people do this (myself included).
These files are supposed to be deleted when you close the opened attachment, however this only happens if the email message the attachment arrived on remains open - this is either an opened message in a new window or in the reading pane. When the message is closed (or you wait to preview another message) after the attachment is closed, the temporary file is deleted from the SecureTemp folder. If you close the open message or display another Outlook item in the reading pane but leave the attachment open, the temp file is not deleted when you close the attachment.
Temporary files are created for sorts, hashes, or temporary query results. To track the creation of temporary tables or files, set log_temp_files in a custom parameter group. This parameter controls the logging of temporary file names and sizes. If you set the log_temp_files value to 0, then all temporary file information is logged. If you set the parameter to a positive value, then only files that are equal to or larger than the specified number of kilobytes are logged. The default setting is -1, which disables the logging of temporary files.
You can also use an EXPLAIN ANALYZE of your query to review disk sorting. When you review the log output, you can see the size of temporary files created by your query. For more information, see the PostgreSQL documentation for Monitoring database activity.
Replication slots can be created as part of logical decoding feature of AWS Database Migration Service (AWS DMS). For logical replication, the slot parameter rds.logical_replication is set to 1. Replication slots retain the WAL files until the files are externally consumed by a consumer. For example, they might be consumed by pg_recvlogical; extract, transform, and load (ETL) jobs; or AWS DMS.
When you use cross-Region read replication, a physical replication slot is created on the primary instance. If the cross-Region read replica fails, then the storage space on the primary DB instance can be affected. This happens because the WAL files aren't replicated over to the read replica. You can use CloudWatch metrics, Oldest Replication Slot Lag, and Transaction Logs Disk Usage to determine how far behind the most lagging replica is. You can also see how much storage is used for WAL data.
1. For temporary files, turn on the log_temp_files parameter on the Aurora PostgreSQL-Compatible DB instance. This parameter logs the use of temporary files that are larger than the number of specified kilobytes. After this parameter is turned on, a log entry is made for each temporary file when the file is deleted. A value of 0 logs all temporary file information. A positive value logs only the files that are larger than or equal to the specified number of kilobytes. The default value is -1, which turns off temporary file logging. Use this parameter to identify the temporary file details, and then relate these temporary files with the FreeLocalStorage metric.
It's a best practice to closely monitor your application and see which transactions create temporary tables. By doing so, you can manage the usage of the available local storage capacity. You can also move to a higher instance class for your Aurora instance so that the instance has more available local storage.
Safely creating, using, and removing temporaryfiles requires more attention to detail than mostDevs, Ops, and DevOpses assume. This post summarizesthe various dangers of using temporary files in anunsafe manner, leading to a number of securityvulnerabilities including arbitrary file overwrites,privilege escalation, or information disclosures.
Yes, that seems obvious, but it bears repeating:you should avoid using temporary files wheneverpossible. Temporary files are terriblyconvenient, but they also provide ample opportunity toto shoot yourself in the foot. If there's any way you canreasonably work without temporary files -- for exampleby way of pipes or subprocesses -- do so.
For those not patient enough to read this wholepost, here's the terse summary:don't use temporary files
if you can't avoid it, then:set a restrictive umask
use mktemp(3)/mkstemp(3)
unlink your temporary files via an exit handler
Ok, so you've set your umask, and/tmp/myfile will be created readable only bythe owner (i.e. you). My previous ploy was foiled -blast! But wait, I know (or can predict) the name ofthe file you're going to create, and I have writeaccess to the directory in which you're creating thefile...
To avoid: check for the existence of thefile you're writing to before doing so. If the filealready exists, remove it or use a different filename. You may also wish to create the file in aprivate directory (which itself may need to betemporary). The more complete solution here is to usemktemp(1). More on that below.
Not only can I read the data you're generating(which may or may not be a concern to you), but bystaging the symlink attack above, I can also cause youto overwrite any file you have write access to. Ifyou are creating the temporary file as root(which many tools that exhibit this problem do), thenI can clobber any file on the entire system.
Ok, so creation of temporary files is a pain. Youneed to account for existence of the file, use aunique name, protect the file, and later (safely)remove the file again. We already discussed settinga safe umask above -- this remains a criticaland required part! In addition, you can make use ofthe mktemp(3) interface provided by mostprogramming languages (e.g. via mktemp(1) foryour shell).
Safe removal of the temporary files is somethingthat should be done both explicitly by your script /commands as well as by any exit handlers you use (seethis post).Some programming languages also provide convenientlibrary function wrapping mktemp(3) thatautomatically remove the temporary file after e.g.closing of the file handle -- use those!
Yep, that's still a pain, and you still have plentyof room for mistakes. Seriously, try to avoidtemporary files. But if you can't, the above "umask;mktemp; rm" combination is the only reasonableapproach.
But this of course creates another race condition:right after you removed $fname, somebodyelse might have re-created it. Instead, you want tocreate a temporary directory (with suitableprotections!) immediately, then create the requiredresource therein:
If you're still not convinced that temporary filesare more complicated than you thought, here are somemore issues. These do not necessarily pose securityconcerns, but are still so frequently seen especiallyamongst inexperienced developers and students, that Ithink it's worth noting them.
One common mistake is to not use the correctdirectory to create temporary files under. Forexample, I regularly see students write code thatassumes that a given program has write access to e.g.the current working directory. Ok, rookie mistake,easy to fix - just use /tmp, right?
But doing that is not always the right solution,either. By convention and necessity, /tmp isof course world-writable with the sticky bit set,meaning that despite being world-writable, only thefile owner (or root) may remove a file in it. But thedirectory remains world-readable and world-executable,meaning you will at the very least revealthat you are creating temporary files as wellas what their naming schema may be. 2ff7e9595c
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