Splitting a database table into multiple segments for performance or manageability.

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How Does Table Partitioning Help?

I am having difficulty to grab the idea of pros and cons of table partitioning. I am about to start work on a project which would have 8 tables and one of them will be the main data table which will ...
19
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2answers
275 views

Is it possible to force the optimizer to eliminate irrelevant tables in this partitioned view?

I'm testing different architectures for large tables and one suggestion that I've seen is to use a partitioned view, whereby a large table is broken into a series of smaller, "partitioned" tables. 1, ...
19
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2answers
4k views

What is the modern way to partition PostgreSQL across machines, when the data is “naturally partitionable”

After several years of dwelling into the "NoSQL" space, now I have a problem that is quite "relational" in its nature. Today I see data stores with quite different eyes than before. Things like Riak ...
18
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1answer
649 views

Seek and you shall Scan… on partitioned tables

I've read these articles in PCMag by Itzik Ben-Gan: Seek and You Shall Scan Part I: When the Optimizer Doesn't Optimize Seek and You Shall Scan Part II: Ascending Keys I’m currently having a ...
18
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1answer
371 views

Statistics disappear after incremental update

We have a large partitioned SQL Server database utilizing incremental statistics. All of the indexes are partitioned aligned. When we try to rebuild a partition online by partition all of the ...
17
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2answers
4k views

SQL Server does not optimize parallel merge join on two equivalently partitioned tables

Apologies in advance for the very detailed question. I have included queries to generate a full data set for reproducing the problem, and I am running SQL Server 2012 on a 32-core machine. However, ...
16
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2answers
3k views

effective mysql table/index design for 35 million rows+ table, with 200+ corresponding columns (double), any combination of which may be queried

I am looking for advice on table/index design for the following situation: I have a large table (stock price history data, InnoDB, 35 million rows and growing) with a compound primary key (assetid ...
15
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4answers
3k views

SQL large table design

I have a general question about SQL Server 2008 table(s) design. We currently have a table that is over 600GB and grows at about 3GB a day. This table has the appropriate indecies but is becoming a ...
14
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3answers
4k views

Can I move rows between partitions by updating the partition key?

I would think that this would be a fairly simply question, but I've actually had a difficult time finding an answer for this. The question: Can you move rows of data within a partitioned table from ...
14
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1answer
10k views

Index optimization with dates

I have a large table of objects (15M+ row) in PostgreSQL 9.0.8, for which I want to query for outdated field. I want to divide the query by millions, for scalability & concurrency purposes, and I ...
14
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3answers
7k views

Does the partition key also have to be part of the primary key?

I am partitioning a table based on a column that is not a primary key? I've read some conflicting information today on whether the partition column must be a part of the primary key. My gut says no, ...
12
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2answers
29k views

How to partition an existing non-partitioned table

I have an existing table with data: dbo.Test (col1,col2,col3....) ON [PRIMARY] I need to change this table to be partitioned like this: dbo.Test(col1,col2,col3....) ON Ps_Date(Col2) How I can I ...
12
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2answers
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SQL Server 2008 - Partitioning and Clustered Indexes

So let me preface by saying I do not have total control over my db design, so a lot of the aspects of the current system cannot be changed for the purposes of this scenario. Comments about how we ...
12
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4answers
4k views

Table partitioning for archiving data

Scenario: two databases: DB_A and DB_Archive with one very big table called tableA. every day, records older than 60 days are deleted from DB_A and moved to DB_Archive mainly to leave thing ...
11
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1answer
4k views

Database archive solutions

In continuation to a question posted by me on Is it a good idea to move high-volume and highly-accessed tables to a separate database?, am looking out for different techniques/solutions available for ...
11
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1answer
217 views

How can I interpret the results of these DMVs to help me evaluate our partitioning strategy?

Version: SQL Server 2008 R2 Enterprise Edtn. (10.50.4000) In attempt to evaluate our partitioning strategy, I wrote this query to get the access methods against indexes on partitions (in the broadest ...
11
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1answer
461 views

Disk file effects of delete and vacuum

I have a very frequently updated table with 240 million rows (and growing). Every three hours 1.5 million rows are inserted and 1.5 million are deleted. When I moved the cluster to a SSD this bulk ...
10
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3answers
45k views

How do I get a list of all the partitioned tables in my database?

How do I get a list of all the partitioned tables in my database? Which system tables/DMVs should I be looking at?
10
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2answers
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SQL Server 2008 R2 Partitioning - same FileGroup, 1 File, 2 partition_numbers - HELP

It's my first go at partitioning in SQL Server, I learned from the Brent Ozar guide which is fantastic :) A few times I have ran into a weird scenario; when I run: SELECT * FROM ph.FileGroupDetail ...
9
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2answers
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How to best store Google ngrams in a database?

I downloaded google onegrams some days ago and it’s already a huge amount of data. I inserted the first of 10 packages into mysql and now I have a 47 million record database. I am wondering how one ...
9
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1answer
3k views

MySQL Partitioning: Is there a performance tradeoff between number of partitions and size of each partition?

I have a large table (several 100 million rows) that I would like to efficiently partition. My question is whether there is a tradeoff between partition size and number of partitions. As far as I ...
9
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1answer
582 views

Storing and querying rolling data in PostgreSQL

I have a large quantity of weather model data being put into a PostgreSQL database. The machine has 8 cores and 16 GB of RAM. I'm running PostgreSQL 9.3 with PostGIS 2.1. Each table will have a ...
9
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1answer
257 views

Why my database mirror break down after changing file group settings from RESTRICTED_USER to MULTI_USER?

My environment is the following: VMWare 5.5 vitalized server MS Windows Server 2008R2 Enterprise domain and SQL Server 2008 R2 Enterprise. Centralized storage with fibre-channel connection. I have ...
8
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4answers
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SQL Server Partitioning - what to use for partition key?

I've never worked with SQL Server partitioning but I currently faced with designing a database for which the volumes probably warrant it. The system is for coupons. The coupons are to be issued ...
8
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1answer
2k views

How accurate is the sys.partition.rows column?

The system view sys.partitions has a column "rows" that is the total number of rows in a given partition. For a table that is not partitioned (or only has one partition depending on how you look at ...
8
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2answers
209 views

Getting a realistic query plan when partitioning with low volumes of data

We're using partitioning to reduce the amount of blocking our OLTP system experiences due to locks, with a partition scheme that splits the working tables into 100 partitions based on a customer id. ...
8
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3answers
149 views

Why NOT partition?

When would one NOT want to partition a database? (thinking MySQL partitioning) In my case I'll be starting with a couple millions rows, it should grow from there. Primary key on a character field ...
8
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1answer
200 views

To partition or not to partition?

Having already read several questions on SO, external blog posts and manual SO: Foreign Key constraint to partitioned table in Pg dba.SE: Different ways of handling FK to partitioned table in Pg ...
7
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1answer
1k views

Switching Data In Fails with “allows values that are not allowed by check constraints or partition function on target table”

Given the following -- table ddl create table dbo.f_word( sentence_id int NULL, sentence_word_id int NULL, word_id int NULL, lemma_id int NULL, source_id int NULL, ...
7
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3answers
1k views

non-clustered unique indexes on sql server partitions

SQL Server 2008 requires unique non-clustered indexes created on a partition to include the partition field in the index definition. I'm wondering why.
7
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1answer
1k views

Why isn't partition-level lock escalation the default?

In SQL Server, locks are normally escalated from row or page -> table. Starting with SQL Server 2008, a new level of lock escalation was added - partition level. However, this isn't automatically ...
7
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1answer
614 views

PostgreSQL partition hierarchy design for centralized logging

I am looking into setting up logging from all of my servers into a centralized postgresql database. It makes sense to be able to drop logs by date or by host, so I'd like to set it up with ...
7
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1answer
879 views

Full-text index in partitioned table

I have a table with just over a million records with a full-text index. This table has been split in two in the past, and the data older than a certain date is moved to another table with the exact ...
7
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1answer
217 views

Error in partition switching in SQL Server 2014 when migrating a database from SQL Server 2005

I am migrating an old database from SQL Server 2005 to SQL Server 2014. This database has a partitioned table; a scheduled job periodically moves old data from the "online" table to the the historical ...
6
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1answer
7k views

ALTER TABLE … SWITCHing from regular table to partitioned table fails

The code below does the following: Creates a database play_partition in C:\TEMP Creates two identical partitioned tables play_table and archive_play_table Switches play_table partition 1 to ...
6
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2answers
139 views

Does table size matter?

I have a table like this (with more columns though): CREATE TABLE [dbo].[MyTable]( [SnapKey] [int] NOT NULL, [SnapDt] [smalldatetime] NOT NULL, [Company] [varchar](4) NOT NULL, ...
6
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2answers
610 views

Is it worth partitioning a Table by single value in Oracle?

Normally, if you have a column you frequently query a table by, you ought to stick an index on it. But is it worth also partitioning a table by this column, if all possible values are known in ...
6
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2answers
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Making the Oracle optimizer use a virtual column to find out about a partition

I have a large table that has three columns like this: "START_DATE" DATE, "START_VALUE" NUMBER(10,7) "START_DATE_VALUE" NUMBER(18,7) GENERATED ALWAYS AS ( (extract(YEAR FROM START_DATE) * ...
6
votes
2answers
1k views

Recreate Indexes on 1 billion record table

I have a table with over 1 billion records and it has 6 indexes (including Clustered index (ID)). I need to partition this table on a new Clustered index with date column. I have just enough space ...
6
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3answers
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Slow queries on billions-rows-table // index used

Since I'm a young developer and not really skilled in using databases (PostgreSQL 9.3) I ran into some problems with a project, where I really need help with. My project is about collecting data of ...
5
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1answer
1k views

Will table partitioning speed up my queries?

My database is set up with what we call our staging tables and our live tables. Currently for we have about 2 million rows for a table called products. Our customers we call manufacturers load their ...
5
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2answers
2k views

Get a record's current partition

In SQL Server 2008 R2, how would I determine what partition a record currently lives in?
5
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2answers
154 views

Total billions of rows and daily millions of row insert: What database system suits best [closed]

We developed a system with very high volume of data but very simplified data structure. We had only cellX, cellY, timeStamp and value columns. Operations are: Insert 455+ thousand rows per day ...
5
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2answers
2k views

Creating partitions on a production database

I have a production MySQL 5.1 database that is running well but I want to improve query performances. I have never used Partitions and just going through the manuals. I have two tables that involve a ...
5
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2answers
1k views

Oracle partition by interval using persian calendar

Oracle supports Persian (Jalali) calendar in DDL queries, I can easily say: select to_char(register_date, 'YYYY-MM-DD', 'nls_calendar=persian') from my_table; I created a table as: create ...
5
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1answer
5k views

Best way to increase no of partition in SQL Server Table

I am maintaining a database with a big big table, which portioned for each month. There is already tens of partition there but its till January 2013, So its time to create new partitions. Can anyone ...
5
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1answer
727 views

Expanding a partitioned table

I have a table that holds four years of data, where for each month I have a partition that is based on a filegroup with two files. Unexpectedly, I received eight more years of data and prepared the ...
5
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1answer
2k views

Does UPDATE INDEXES work for local indexes?

I have two tables in Oracle 11.2. First is partitioned and has local index (non-prefixed): CREATE TABLE table1 (col1 INT, col2 INT) PARTITION BY LIST(col1) ( PARTITION p1 VALUES(1), PARTITION ...
5
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2answers
158 views

Mechanics of partitioning

Imagine the following hypothetical database structure. Basically it's a top down structure (Country has Orders, Order has OrderLines, OrderLine has ShipLines, etc...). I want to partition my SQL ...
5
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1answer
200 views

Managing and speeding up queries on PostgreSQL table with over 3 trillion rows

I have time series data which spans over 10 years and has over 3 trillion rows and 10 columns. At the moment I use a PCIe SSD with 128GB of RAM and I am finding that querying takes a significant ...