Questions tagged [storage]
For questions about the persistent storage of database data.
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Could MySQL perform better on a 10GB network storage with raid vs local HDD?
Compared to using a HDD on local computer and do many MySQL read / writes on it, could it have more queries per second if I install 10GBe network cards and I store the MySQL data on a raid network ...
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Table with smaller data types seems to take more space on disk?
I have these two identical tables:
Table "public.region"
Column | Type | Collation | Nullable | Default
-------------+----------+-----------+----------+---------
...
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More columns vs. more rows to optimize storage and performance?
I have a table with this structure:
ticker VARCHAR NOT NULL,
interval VARCHAR NOT NULL,
ts TIMESTAMP WITHOUT TIME ZONE NOT NULL,
price ...
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Primary File Organization in DBMS - Files of ordered records (sorted files)
"Fundamental of Database Systems", 3rd ed. by Elmasri and Navathe, page 136 says:
"We can physically order the records of a file on disk based on the values of one of their fields [...]&...
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Microsoft SQL server storage best practice on Windows server vm with hybrid storage
I have a windows server VM, with a combination of HDD and SSD storage, the SSD storage capacity is limited to 50 GB, but HDD storage capacity is high.
What is the best way to share these storages to ...
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Why JSON indexing take less storage than multiple columns in MySQL 8?
I am doing a quick performance comparison for 10 000 rows on MySQL 8.0.27 between
a table multiple_cols with 2 columns num INT and str CHAR(200) having each an index,
a table json_indexing with 1 ...
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2
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63
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Determine Ideal Collation Set for correct data storage
Alright so I have a MariaDB DB and I've just noticed some weird storage issues, like the following:
My JSON columns (which in MariaDB are LONGTEXT) have an automatically set collation of utf8mb4_bin. ...
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Size of data in DB is much larger than size of data dumped to disk
I have a table that contains 99.9% of the data in the database. When I query the size of the table and database, I get:
mydb=# SELECT pg_size_pretty( pg_database_size('mydb') );
pg_size_pretty
------...
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What exactly is a persistent storage database?
I have to load some stuff(data) onto a "persistent storage database." The assignment says:
'Please use some sort of network-accessed database like MySQL or Cassandra, but it may be any such ...
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How to use raw disk for MySQL data?
I'm having trouble getting MySQL 5.7 to use raw disk (a block device, bypassing the filesystem) for its data. My understanding of the documentation is that basically, first time mysqld is executed, ...
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Performance of temp db files on SAN
It is generally recommended to put the tempdb database on disks that differ from those that are used by user databases.
I have 4 databases on my sql server, ranging from 5GB to 300GB in size.
D: drive ...
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Are TOAST rows written for UPDATEs not changing the TOASTable column?
Imagine I have a table in Postgres 13 like this:
CREATE TABLE public.people (
id integer PRIMARY KEY,
full_name character varying(255),
bio text
);
I then insert a row with enough ...
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I/O connection lost on Oracle VM (KVM)
This is the situation:
2 nodes RAC with ASM.
Both nodes are VM based on OVM.
At some point, we observed one node losing connection with 4 disks (/dev/... etc etc).
Every db on the node, goes down.
...
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Oracle Storage Full, How to release space?
i have and AWS RDS Oracle Database wich its storage is full, looks like the cause is SYSAUX tablespace with 10.2GB size
The largest object inside SYSAUX is: WRI$_ADV_OBJECTS (TABLE) checking the table ...
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How to reduce big size database files (Data File ) SQL Server without SHRINK?
I found a couple of 'question' regarding shrinking big datafiles but I think that is not very accurate to my situation. So here is my question
I have a big database with almost 8TB of Data File Size ...
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I want to drop existing table space and add the freed space to the new table space in oracle
I want to drop existing table space and add the freed space to the new table space in oracle.
I am trying drop an existing tablespace on oracle db, and then use the freed space for a new table space. ...
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What are the differences between Heap File Organization and Sequential File Organization (Pile Method)
I was learning about File Organization in DBMS, but i found that the Heap File Organization and Sequential File Organization (Pile Method) have the same definition (or maybe i couldn't find any ...
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2
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42
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How to store a table with 1000+ columns, which are mostly null
Today I have to restart a projet and due to a specificity of the business (real estate), I will have to store a table for house/apartment/hangar/wahetever. But a single row can contain more than 1000 ...
SKMTH
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Postgres Database flagged as STORAGE FULL whereas there's 45 Gb available
I will start this post by stating that I am not very experienced in database administration, please accept my apologies for any unclear explanation you may find below.
We have a replica postgresql ...
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34
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Character type for a column with expected natural duplicates?
I've noticed that some non-relational databases (e.g. Druid) have a feature where if a given string is stored in multiple rows, the physical storage keeps only a single copy (per some unit of storage)....
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Storage configuration for faster queries [closed]
Please advise on setting up storage allocation for a new SQL Server 2019 machine.
Ryzen 7 8Core with 64GB Ram
4 local drives (2TBNVMe PCIe4 + 1TBNVMe PCIe3 + 2TBSSD + 4TBHDD)
I am going to allocate ...
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3
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RMAN configuration suggestions to help save our storage space?
To preface...
Our Senior Oracle DBA has just recently passed away, and I've been taking over. My level of experience is just a junior level. So there is a lot I still don't understand. So I appreciate ...
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Why database has char data type when varchar is more efficient?
I understand the basic difference between CHAR and VARCHAR datatype that CHAR takes up fixed length whereas VARCHAR takes up space based on the content being stored.
But if VARCHAR is so efficient in ...
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What steps we need to perform from DB end in case of storage migration?
What are the impacts / steps from DB2 DB side before VMware SvMotion Storage migration ?
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Pointing the database secondary data file towards a network drive
I have a 2 TB database and the Data Drive has filled up. My network team cannot expand the drive nor provide another drive so that the secondary data file can be pointed towards that. My question is ...
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3
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SQL Server - Benefits of splitting databases across different logical drives
We're about to start a project to migrate a large DWH to new physical servers in a new data centre. The current server spec is SQL Server Enterprise 2016 SP2 running on Windows 2012 R2. The new ...
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Azure Virtual Machine - local temp storage (D: drive) - how much IOPS it can handle?
Virtual machine size DS3 (under older generation sizes)
Azure Portal (when deploying VM) shows that DS3 supports up to 16 data disks / up to 12800 IOPS - thats fine,
But what I am interested in is it'...
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762
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SQL Database size incorrect and database file growing while empty
RESOLVED - SOLUTION AT BOTTOM OF POST
PROBLEM
I have a database data file showing as 200GB on disk, and 200GB allocated space in the database properties. sp_spaceused also shows 200GB allocated. All ...
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150
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SQL Server storage - evaluate the number and types of read write operations for the existing deployment
Training for SQL Server, one of the questions in Learning material says:
Before migrating on-premise SQL Server deployment (single server) to Azure VM, you need to evaluate "number and types of ...
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215
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ORACLE ASM present one or more LUNs?
I have the following question regarding the allocation of disks or LUNs to ASM in Oracle, specifically, I have an Oracle 18c DB in Cluster and I have created several diskgroups, now, I need to ...
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How do you change the storage parameters of a already made table (sql developer)?
Summarize the problem
I have been given 6 tables that have all been created already and I was told to change the storage parameters of those tables. the issue I run into is that I can only change ...
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Issues (Other Than Disk Space) For Using Operating System Partition
Other than accidentally filling your entire C:\ drive with data, are there any other considerations for using the OS drive for data files? Most answers are simply "don't do it", but I'd ...
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SQL Server placement of Files SAS SSD vs SAS HDD
I've got a new server which will host MS SQL Server Virtual Machine along with Other VMs on HyperV. SQL Server will account for most(70%) of the Load.
The server has below Storage:
a. 2 x 240GB Read ...
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SQL Server & Storage Question - What's the right choice? [duplicate]
I am a young DBA from Germany and I am the administrator for our customers SQL Servers.
I have a question and I really hope that I can explain this in English words. 😃
At the moment I am reading ...
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What is the point of encryption at rest?
I am wondering what is the point of encryption at rest?
It is said that a hacker cannot steal the database and look through it. I'm afraid that it does not protect the database while the key is stored ...
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Best practices for SQL Server block size while formatting disks for data and log files
What is the current best practice or general guidance on formatting the filesystem for SQL server database files.
Currently we have SQL Server file system, NTFS formatted with 64KB block size based on ...
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31
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db choice for activity log
I'm working on a geo-replicated web platform, composed of an ecosystem of microservices.
We need to improve and rework the user activity tracing pipeline and I'm looking for "the best" ...
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TempDB Log File Growth - questions
Problem:
On one of the production boxes, TempDB transaction LOG file grew unexpectedly, filling the drive
It was 32 GB but now it is 240 GB
Questions:
What is the mechanism of TempDB log file usage ?
...
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varchar(n) size?
When I use varchar(5) in a INSERT query it means that the attribute in the table will take exactly 5 bytes in memory? (Given that one printable character takes one byte)?
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Provisioning SQL Server 2019
I'm provisioning a SQL Server 2019 build and have been allocated a virtual server running Windows Server 2016. It has 4 virtual processors and I have 410Gb of drive space to work with.
My build has to ...
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214
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Does large text datatypes reserves storage on disk?
I'm design an DB for an app, in a table there is a column MEDIUMTEXT which according to mysql doc can storage on disk upto 16MB.
So my question is if I'm storing a text of 1Mb in this column, will it ...
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SQL Server sharing drive location
DBA newbie here. Did some searching online but cannot find a definite answer on this.
Is it acceptable to share the drive where .MDF files reside with other non-SQL Server files such as applications ...
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MySQL - storing 162 million rows in 1 table as the result of an IFNULL query
I'm working on a legacy web application which uses a MySQL (5.5.65-MariaDB) database which is hosted on a server running CentOS Linux 7.7.1908.
The application is a database of chemical substances and ...
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Storing data for machine learning in MySQL
I am currently in the process of developing a machine learning application, where my users can upload their own data to train models. Furthermore, the users must be able to extend their uploaded data ...
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MYSQL storage increasing unexpectedly (RDS)
I am total newbie to database game.
& I am using mysql 8.0 RDS 20GB free tier.
I don't have much data on it.(just 300 Mb)
But I always get a mail that you have exceeded 85% of storage limit.(...
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MySQL 8.0 table with JSON column that uses JSON "merge" operations has 500k rows but analyze table shows 7MM
I have a database table that according to TABLE STATUS has 7MM rows, but when I SELECT COUNT(*) it only has 500k rows.
This is a problem because table growth is increasing and we're running low on ...
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What would cause a table with 80,000 records to use 145GB of space?
I have a table that gets inserted and deleted from every day. On average the record count is 80,000. Roughly 20 fields, 10 of which are VARCHAR(4000) however most of the records have those fields ...
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What is the difference between PAGEIOLATCH_* and IO_COMPLETION?
according to this blog:
SQL Server Books online defines IO_COMPLETION as “Occurs while waiting for I/O operations to complete. This wait type generally represents non-data page I/Os. Data page I/O ...
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SQLite Internals - Records
Hey I'm trying to wrap my head around SQLite data storage, specifically how it is storing Records. I've found a book The Definitive guide to SQLlite, where the author explains internal record format (...
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Is it possible to Increase storage performance in azure vm using disk striping?
Given the following Azure VM:
E8s_v3 (8 cpu, 64 GB RAM, 12800 IOPS, 192 MBps)
I added 2 SSD Premium drives, one for data (1024 GBs / 200 MBps / Host Caching enabled read-only) and one for Logs (256 ...
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