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34
votes
5answers
20k views

Measure the size of a PostgreSQL table row

I have a PostgreSQL table. select * is very slow whereas select id is nice and quick. I think it may be that the size of the row is very large and it's taking a while to transport, or it may be some ...
16
votes
2answers
34k views

How do I shrink the innodb file ibdata1 without dumping all databases?

InnoDB stores all tables in one big file ibdata1. After dropping a big table, the file is keeping its size no matter how big the table was. How can I shrink that file without having to dump and re-...
15
votes
3answers
4k views

Why might a table's data space take up 4x the size of the raw data?

I have a table with 490 M rows and 55 GB of table space, so about 167 bytes per row. The table has three columns: a VARCHAR(100), a DATETIME2(0), and a SMALLINT. The average length of the text in ...
11
votes
4answers
36k views

Query to report disk space allocation and used space

We are using 6 databases in total for an application, and we can only share 4TB of space among all 6 auto-grow databases (via SAN storage). I'd like to write a query (report) for a single database ...
11
votes
5answers
577 views

SQL Server Backups - A couple of questions

We run our weekly backup job at 9pm on Fridays and we are experiencing a couple of issues with regard to disk space (which gets perilously low at times) and performance. We're looking at streamlining/...
10
votes
2answers
1k views

Strategy to handle an SQL Server DB with too many files (BLOBs) in it?

Scenario: SQL Server 2005 database servicing an ASP.NET application (on a separate web servers). Database: DB has about 5GB of "normal" data in it, and about 15GB of "files" (e.g.: a 200k PDF stored ...
10
votes
1answer
2k views

PostgreSQL: Disk space not released after TRUNCATE

I haveTRUNCATEd a huge (~120Gb) table called files: TRUNCATE files; VACUUM FULL files; The table size is 0, but no disk space was released. Any ideas how to reclaim my lost disk space? UPDATE: The ...
9
votes
1answer
18k views

Safe way to truncate SQL Server Error Log

We are running out of space. What is the safe way to clear the error log?
9
votes
2answers
3k views

What effect will reducing the size of a varchar column have on the database file?

We have a number of tables in our database that have VARCHAR(MAX) columns where a VARCHAR(500) (or something much smaller than max) will suffice. Naturally I want to clean these up, and get the sizes ...
8
votes
2answers
8k views

How to delete a Backup from a backup set in SQL Server 2008 R2

The title pretty much sums it up. We are running out of space on our backup disks, and need to remove old backups out of the set. I can't seem to find any information on this.
8
votes
1answer
95 views

How to reclaim space taken by an index that partially built and was terminated by a power outage

I'm running postgres (postgis) 9.4.2 on a mac (10.10.4). I've got a couple big tables (several TBs). During an index build on one of them that takes about a week, I watched the available HD space ...
7
votes
3answers
1k views

Get MS SQL Server to release disk space

A poorly managed database table has grown to be enormous. 48+gigs of orphan records. I am trying to clean it up and put my dangerously full hard drive back to a normal state. I will be deleting approx ...
7
votes
1answer
5k views

VACUUM returning disk space to operating system

VACUUM usually does not return disk space to operating system, except in some special cases. From the docs: The standard form of VACUUM removes dead row versions in tables and indexes and marks ...
7
votes
1answer
8k views

Understanding block sizes

My question targets Postgres, but answers might just be good enough coming from any database background. Are my assumptions correct: Disks have a fixed block size? RAID controller can have a ...
7
votes
2answers
27k views

How to free up disk space? which logs/directories to clean?

I want to free up the disk space on my Linux machine. I've drill down the space usage and found that the following directories have a big size /u01/app/11.2.0/grid/cv/log /u01/app/11.2.0/grid/log/...
6
votes
1answer
258 views

Running out of disk space running MySQL query

I have been trying to create a "gaps and islands" identification routine in MySQL. See the previous question regarding setup here and computational resources required here. I increased the RAM of the ...
5
votes
2answers
8k views

PostgreSQL: Query for location of global tablespace?

I have been trying to make our database clients pro-active about not filling up the partition on which the database they are using resides. As all our clients are on the same host as the database ...
5
votes
1answer
341 views

For alignment optimized table is bigger than original table - why?

In another question I learned that I should optimize the layout from one of my tables to save space and have better performance. I did this, but ended up with a larger table than before and ...
5
votes
2answers
7k views

Freeing disk space after dropped database

I'm working on a dev system, and I have been restoring to a database, say "foo", that I'm using for dev purposes. As I'm working through the kinks, I've just been running DROP DATABASE foo. However, I ...
5
votes
2answers
144 views

reporting space consumption to files in filegroup - how to reverse-engineer the algorithm spreading data across files

I would like to know how to calculate the distribution of data consumed per file in a filegroup, back to the index (HEAP, CLUSTERED, NONCLUSTERED) storing it. My intention is to define which I/O goes ...
5
votes
1answer
2k views

PostgreSQL strategies to deal with disk filling up

I'm using PostgreSQL (8.4) to store data produced by an application making frequent inserts (in the table structure described below). The database keeps growing with time and, since the newer data is ...
4
votes
1answer
410 views

How large are blocks of data in SQL Server?

I'm working in SQL Server 2008 R2 and have created a query that gathers and sums the total of data files and log files' sizes. However, I can't find how much actual disk space a single block of SQL ...
4
votes
3answers
583 views

Disk Space usage

Is there a way i can get a report or create a custom report in sql server 2012 which can update me with disk space available & actual disk space for listed drives twice or once a day. I need this ...
4
votes
2answers
928 views

Index Generation in Postgres

We have a database with a single table made up of around 700 million entries. We update the database by adding new entries on a server then transfer the server to the production server using pg_dump: ...
4
votes
1answer
36k views

How to Recover an InnoDB table whose files were moved around

So I have a test db server that was setup on a replication stream. Over the name an optimize came through that quickly filled up the space on the slaves datadir. Mysql dutifully was just waiting for ...
4
votes
4answers
4k views

Empty strings in VARCHAR(MAX) consuming space which cannot be recovered

I have a table with a non-nullable VARCHAR(MAX) column where every row contains an empty string (third party database so I can't change it). I see a huge amount of space use, over 15GB for 1 million ...
4
votes
2answers
279 views

Moving data from table with VARCHAR(50) fields to table with numeric fields increases table size

I want to understand why migrating data in a table with all VARCHAR(50) fields to a table with optimized smaller types caused the new table (containing 61,065,164 rows) to be 4.46 GB, which is larger ...
4
votes
1answer
2k views

Postgres on Engineyard space at 100%, pg_xlog filled up with files

I have a database that is growing rapidly. VERY rapidly. My /db directory is at 100% now, and there are a bunch of new files in pg_xlog. My background is in Oracle and MySQL. I do not know what is ...
4
votes
1answer
34 views

Howto query all files, their fill level and additional drive info with one query?

I need a query that puts together the following results: one row per databse file across all databases additional columns with information about the locigal drive the file is on information about ...
4
votes
1answer
215 views

Is there some drawback to define SPARSE columns?

I have a table which has a lot of NULL values in columns. But some columns don't contain NULLs at all (although nullable). Is there some drawback to declare all of these columns as SPARSE?
4
votes
1answer
4k views

Drop user did not reduce size of tablespace file

I have a development environment in which I frequently copy a certain schema. When I'm done with the copy, I will use OracleEM to drop that user/schema. My problem is that this does not seem to ...
4
votes
1answer
860 views

What are all the reasons/possibilities that may fail to release disk space occupied by TEMPORARY table?

We're using PostgreSQL v8.2.3. Ours is a web-based application and we're using pgpool-II v 2.0.1 purely for connection pooling (we don't use other features of pgpool like Replication, Load Balancing, ...
4
votes
2answers
4k views

Partitioning and freeing disk space

I am running MySql innodb with innodb_file_per_table. As a daily script, I would like to create a new partition for a set of tables, as well as delete yesterday's partitions. What command would need ...
3
votes
2answers
1k views

space usage on sys.allocation_units and sp_spaceused

It is a known fact that the DMVs dont hold accurate information regarding number of pages and count of rows. However, when you have the stats updated, I can't see why they wouldn't. I am working on a ...
3
votes
3answers
3k views

Monitoring free space in SQL Server data files

I have manually resized mdf/ndf files to a big size to avoid autogrow operations on SQL Server databases. Since the files are bigger there is very little free space on disk partitions and the ...
3
votes
2answers
7k views

Disk space full but logical space available in database

We have a fairly big MS SQL 2008R2 database that resides on a SSD drive. The drive itself only has ~110Gb of space, and the database files are the only files on the drive. The database is in "Simple" ...
3
votes
3answers
6k views

Can I specify a different disk for a specific MySQL table?

I use my home machine as my personal database for my hobby analytics project. This machine has an SSD for the main drive where MySQL stores its data. It also has a secondary hard drive that is ...
3
votes
2answers
96 views

Collect disk space metrics for whole SQL Server instance

I am quite new to SQL Server. I would like to collect database disk space metrics for the SQL Server instance as a whole. I have found a code sample that can collect disk space information per ...
3
votes
2answers
282 views

What exactly is written to transaction log?

Here's the scenario: DB with Simple recovery model, Roughly 14 GB of data (~80 million rows), INSERT ... SELECT statement into empty table with 7 non-clustered, non-unique, single column indexes and ...
3
votes
2answers
598 views

What is the difference between Used and Allocated space?

I am learning Database operations and I have found a couple of resources online that have given me a loose understanding, but I still couldn't explain the difference myself. Explain like I am five ...
3
votes
1answer
117 views

Reclaim disk space from dropped column without downtime

I have a heavily used table (with around 5 million rows) in a PostgreSQL database in which I want to drop a column and reclaim the space the column used. The docs suggest doing a table rewriting ...
3
votes
3answers
185 views

Log File Management - Space on Disk

At our organisation we have several non-Production environments where Developers run free and wild with TSQL code and databases. The DBA team do not normally monitor or maintain them. Recently several ...
3
votes
1answer
575 views

Postgres: check disk space taken by materialized view?

I know how to check the size of indexes and tables in Postgres (I'm using version 9.4): SELECT relname AS objectname, relkind AS objecttype, reltuples AS "#entries", pg_size_pretty(relpages::...
3
votes
2answers
318 views

Will reindexing use the empty space or just grow table?

I have a table which is 170 GB and it has 98 GB of free/empty space. The free space was created by a massive deletion. If I run DBCC REINDEX or ALTER INDEX REBUILD, will the index use that free space ...
3
votes
1answer
1k views

Huge MSDB database

I have a very large MSDB database and have been working on clearing this out and setting up maintenance tasks - something my predecessor should have done years ago! So far I've managed to truncate ...
3
votes
2answers
1k views

Get disk space percentage free with SQL Server 2005?

I am currently using SQL Server 2005 and (undocumented I believe) master..xp_fixeddrives to get free space on my database volumes as part of my monitoring. However, this only gives me an absolute ...
3
votes
1answer
691 views

Database server down: file /dev/vda1 used up all diskspace

My database server went down last night because there was no diskspace available. I checked what used up diskspace and it was 28GB by /dev/vda1 I have no clue what this is. The database all together ...
3
votes
1answer
383 views

How do completely empty columns in a large table affect performance?

I have 400 million rows in a Postgres db, and the table has 18 columns: id serial NOT NULL, a integer, b integer, c integer, d smallint, e timestamp without time zone, f smallint, g timestamp without ...
3
votes
1answer
200 views

How do databases deal with file system fragmentation?

Especially analytic databases that try to optimize for queries that scan large portions of tables instead of randomly accessing specific rows. For example Redshift has a concept of a sort key that, ...
3
votes
2answers
948 views

SQL Server 2005: Full-text search space requirements

Is there a way to calculate the physical drive space required for a full-text search catalog? Space is cheap, but I'd like to know what I'm getting into. I'm looking at a table of about 200 articles ...