The name given to the process of encoding data such that it uses lesser number of bits as compared to the original representation.

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16 views

error recovering pg_dump compressed file

I produced this backup: pg_dump -v -Fc -Z5 -f thebackup.dmp.gz thedb I can't open the dump with gzip, 7zip... I could recover the same files in the past without using -Fc parameter. Is it possible ...
3
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2answers
115 views

Export a table and zip with password

I would like, from TSQL, to use a view to extract data from a table, output it with BCP, then use non 3rd party tools to ZIP it with a password and AES encryption. Optionnally, I could use a 3rd party ...
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0answers
21 views

Estimating compression ratio for SecureFile LOBs?

We made a migration from Oracle 10 to 11.2. Our lob objects are currently stored in the original LOB storage architecture. But 11g introduced the SecureFile storage architecture and we want to use ...
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1answer
445 views

Mongo Db server status with wired Tiger

I was testing my DB with Mongo 3.0 wiredTiger setup. After restoring my database with wiredTIger i ran db.serverStatus. I found following in console output. "bytes currently in the cache" : ...
5
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1answer
69 views

Postgres: Is migrating old records to separate table and creating new aggregated records a good strategy to improve search speed?

I have a table with 1M+ records. New records are created and updated each day each time an event occurs for each type of event (which there are many). I frequently need to find sums across many ...
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1answer
54 views

Sql Server thinks I have different Data Compression when swaping partitions

I am setting partition switching for my database. I created a script using SqlCmd variable so that the same script would make both my source and target tables for partition swapping. Here is an ...
8
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1answer
293 views

What is the different between compression on the PK vs. on the Table?

Data compression can be set on the table: CREATE TABLE dbo.SomeTable( SomeId [bigint] NOT NULL, OtherId [bigint] NOT NULL, IsActive [bit] NOT NULL, CONSTRAINT [PK_Some] PRIMARY KEY ...
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0answers
51 views

Data compression within Internal Tables in SQL server 2008R2

We are doing downgrade from enterprise to standard for couple of servers which are not using any enterprise features: For one of our TFS(Team foundation server) database TFS_resx, when we ran ...
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58 views

What are the compression options for storing large amounts of text in Postgres?

I need to store large amounts of text in Postgres, mainly command logs and the output of long running commands and need to know if there are some settings that could help compress the data ...
4
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1answer
91 views

IO request time and less write latency

I am facing issues related to constantly growing log file due to which I am getting error. When I checked SQL Log I found below messages (error log is filled of these messages almost 90%) SQL ...
4
votes
1answer
156 views

Page compression not working?

I have created a table where I have around 100 partitions (per month), all of them are configured to use page compression. After that I'm inserting data to this table month by month. I now would ...
1
vote
1answer
31 views

How can I create a database where entries are compressed files searchable by index? [closed]

I am trying to design a database solution for logging where the search indices are dates (days), and the values are zipped files. I am doing this because the sheer number of logs I am processing is ...
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2answers
203 views

Compressing partition - what about index?

To save space on disk I want to compress some partitions of my tables: alter table TEST_TAB move partition TEST_TAB_2014 compress for all operations; I have also indexes on this partition. Should I ...
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0answers
56 views

Backup File Size Almost 50% of Database File Size with TDE Enabled

I'm really hoping someone can help shed some light on this for me. I receive a full backup of a very large database once per week from a vendor. It contains transactional data which we then load into ...
4
votes
1answer
312 views

GZipStream/DeflateStream compressions alternatives

I have created a simple CLR functions for compressing/decompressing NVARCHAR columns: [SqlFunction(DataAccess = DataAccessKind.None, IsDeterministic = true)] public static SqlBinary Compress( string ...
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48 views

MySQL blob removes last bites when selecting in some strings

When I retrieve blob it get cut from the end a little. Most strings are ok, but some got cropped for several last charecters. echo $data, '<br />'; db_execute("UPDATE table SET blobcolumn = ...
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1answer
32 views

Will canceling InnoDB compression that's already in progress corrupt data?

I have a 155GB table that is in the process of being compressed. ALTER TABLE $table_name ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8; This compression has been running for a long time and is impeding my ...
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1answer
172 views

Correct place to put very large text field for mysql/mariadb

I have an app where a queue is being processed, Each time an entry is processed the result is stuck in a separate table. The queue table gets inserts and updates, the result table inserts only. The ...
5
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1answer
622 views

Alternative way to compress NVARCHAR(MAX)?

I am trying to compress some tables that have NVARCHAR(MAX) fields. Unfortunately, the row and the page compression do not have the desire impact (only ~100/200 MB saved for 20 GB table). Also, I am ...
3
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1answer
118 views

sp_estimate_data_compression_savings for column store compressions

Is there a way to get compressions saving for column store and column store column store archival compression? In order to check these compressions saving I have to drop all clustered and non ...
5
votes
1answer
952 views

Benefits of Barracuda and Compression

I've been reading about MySQL's file formats Antelope and Barracuda a while ago, and I wonder if I could benefit with having Barracuda and Compression. My server is currently using Antelope, as it is ...
3
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1answer
519 views

ROW_FORMAT - COMPRESSED vs COMPACT vs DYNAMIC

In MySQL InnoDB, what is the difference between COMPRESSED, COMPACT and DYNAMIC for ROW_FORMAT? What are the benefits between each other?
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1answer
65 views

Moving Clustered Index to new filegroup results in excessive filegrowth

I've Moved the clustered index on large tables to new filegroups to defrag, compress, and to recover space more easily from the original "primary" filegroup. Problem: A 315GB compressed Clustered ...
2
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1answer
94 views

Best Practice in storage allocation for compressed and partitioned tables

I have a fairly large database that basically consists of one table, this table is paritioned by month and all partitions are compressed with page compression. After the initial load of the data there ...
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1answer
87 views

pg_basebackup: could not set compression level -1

When trying to run pg_basebackup I received the following error message: pg_basebackup: could not set compression level -1 (null) using the -z option. I received a similar error message when trying ...
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1answer
186 views

Data compression with in memory OLTP

Will having data compression enabled decrease the amount of memory used by an in memory OLTP table? If yes I assume the CPU workload will increase.
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2answers
65 views

Determining the tables and impact of a large number of SPs

I'm trying to track down what is causing some response times to increase when data is compressed by page compression, when the system is not CPU bound and 95% of responses see a decrease in response ...
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2answers
510 views

Restoring database from a server that uses data compression

In our environment our production server is using MS SQL Server 2008 Enterprise Edition. We have a development and test server that runs MS SQL Server Standard Edition and the table structure between ...
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1answer
147 views

Impact of replication compression & encryption on performance, traffic?

What is the impact of MySQL compressed-slave-protocol on replication traffic? According to High performance MySQL it can lower the traffic to a third of the same replication without the compression. ...
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1answer
2k views

Compressing Base64 Encoded Image in Database Field. Table Size too Large

Database Info Database Type - Percona MySQL. Table engine - InnoDB. I have a database table that is currently using 17GB at 400,000 rows. This size is mainly because I'm storing a 40kb base64 ...
2
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1answer
281 views

Does Windows Server File Compression slow Oracle DB performance?

I'm starting a new a new contract and I get to troubleshoot their Oracle instance... I'm more apps and sql, but I'll be trying to figure out their crashes and slow performance. Go figure. I can ...
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2answers
395 views

T-SQL script to perform a compressed backup with maximum compression level [duplicate]

I have a database with full backup of almost 2GB. When I perform a full backup (without compression) and then compress it with winrar it become 140MB, but when I backup WITH COMPRESSION syntax the ...
4
votes
2answers
798 views

TokuDB optimize table does not reclaim disk space

Was running an optimize table command against one of my tables about 11Gig in size, surprisingly used disk space grew by 2Gig immediately after optimization process finished. I would expect the ...
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1answer
143 views

Are string columns with very few different entries automatically compressed?

We have a table which contains a column with only a dozen different strings in it. Is there anything I need to do in order to get the DB to compress this information? We don't have too much disk space ...
2
votes
1answer
786 views

SQL Server 2012 Page Compression - Determine compression ratio?

We're using SQL Server 2012 and have page compression turned on for a number of our larger tables. Is there a way we can determine the compression ratio we're getting? We'd like to be able to ...
2
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0answers
557 views

Understanding how sys.dm_exec_requests represents queries being rolled back

I'm not sure whether this was an actual problem or just a normal situation where I needed to wait for rollback to finish. In either case, some insight would be appreciated. Background details I ...
5
votes
2answers
1k views

Clustered index compression vs table compression - are they the same thing?

If I set compression (either page or row) on the clustered index of a table, is that the same as setting compression on the table? SQL Server provides options for doing both, which suggests that they ...
1
vote
1answer
615 views

Alter table move taking long time

I'm currently trying to compress a table in Oracle with the following statements: ALTER TABLE MYTABLE COMPRESS FOR OLTP; ALTER TABLE MOVE; My question is: the MOVE operation is taking forever and ...
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vote
2answers
7k views

What is the most effective way to compress and store a SQL Server backup? [closed]

I've been doing some testing of different methods for compressing and storing SQL Server backups (using SQL Server 2008 R2 Enterprise edition), and I'm wondering what the most effective compression ...
8
votes
1answer
2k views

Is SQL Server data compression categorically good for read-only databases?

Some literature on SQL Server data compression I read state that the write cost increases to about four times what would normally be required. It also seems to imply that this is the primary downside ...
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votes
2answers
188 views

Can I restore an uncompressed differential backup after a compressed full backup?

If we enable compression on database backups (because the database backup size is huge) but don't enable it on differential which are relatively small in size, will a restore work? Because the full ...
5
votes
2answers
337 views

When should tables NOT be compressed

We have two servers. One we just compressed, but I took over this little project and this guy says some tables are not good candidates. As with many others, performance is -critical-. Is it accurate ...
4
votes
1answer
2k views

Compress backup file using T-SQL

Is it possible to compress a backup file to .zip (or another) in a stored procedure invoked from a maintenance plan? My maintenance plan contains these steps: check DB (consistency, re_index, maybe ...
1
vote
1answer
229 views

Database size not reduced after compressing tables

Using Data Compression, my table size was reduced from 1770 MB to 250 MB, but the database size was not reduced. Why?
4
votes
1answer
607 views

Compressions vs shrinking a database

Is compression and shrinking a database in SQL Server same? If I compress a table, will it decrease query performance and DML?
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2answers
2k views

Is data retrieved from SQL Server compressed for transmission?

Is data retrieved from Microsoft SQL Server compressed? If this is controlled by the connection string, is there any simple way to tell if any particular app is using it? I'm examining analysis ...
1
vote
1answer
388 views

Which Database to choose: MySQL or Oracle

I have an application generating time series data (32 channels, 22KHz, 6 secs) once a minute. These have to be stored in a database. At the moment I'm using MySQL with InnoDB tables ...
7
votes
2answers
2k views

PAGE compression in SQL Server effect on running queries

I am planning to apply PAGE compression to some of the big tables in my database (DW to be precise). These tables are fairly big with over 15 Billion rows. When I applied the compression in test ...
2
votes
1answer
282 views

Why 2 allocation units during online index rebuild to different file group?

I'm in the process of rebuilding the clustered index of a big table to a different file group. I'm monitoring the rebuild process using sys.system_internals_allocation_units. I'm 3h in but not done ...
3
votes
2answers
2k views

Does adding page compression to a table also compress existing indexes?

I am creating a series of new tables that will have page level compression enabled. Will this affect the indexes as well, or will I have to also specify compression when creating the indexes? create ...