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

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Incorporating Partition Views into a Data Warehouse

I've read some material on how to accomplish this but I want to validate it before proceeding. My understanding is that you: 1) Define the table that we want to add into the partition with the ...
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1answer
21 views

Want to create partitions of a MySQL table and change the charset of new partitions

I have a database table which contains large amount of data. I have written a script to create new partitions every week and drop old partitions (which are of no use). Currently, I have a column in ...
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1answer
29 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 ...
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20 views

Sharding TPC-C Benchmark with MySQL Fabric

Currently I have a setup of 5 mysql database nodes (db01 ~ db05). MySQL Fabric and backstore have been installed and running in db01. I configured one global_group (i.e. group_02) with db02 and three ...
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1answer
68 views

Is DBCC SHOWFILESTATS an accurate way to see unused space?

We have a few tables each with near 100 million rows of data. A co-worker has these tables setup with partitions based on a date field. Our disk space is starting to run low and knowing that ...
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1answer
26 views

Are there any inherently non-partitionable datasets?

Are there any practical datasets that, by their nature, cannot be partitioned in any practical way? I am wondering about this because such datasets would be ill-suited to scaling out on commodity ...
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1answer
61 views

Oracle Partition Table Space Issue

I have a table with list partitions on it. When i insert data i see that all the partitions have default initial size of 8 MB and I also noticed that when i truncate full table and check size it still ...
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1answer
41 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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9 views

Modulus calculation for compound primary keys in MySQL Cluster (and other sharded databases)

In MySQL Cluster, and generally in sharded databases, how is a compound primary key's modulus calculated? Say, for example, there are two tables that have primary keys like so: CREATE TABLE Orders ...
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1answer
21 views

MySQL 5.1: How to rollback partitioned table

I have partitioned a table on the basis of one flag column have value either 0 or 1. Now, I want to roll back these tables. How can I do this?
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1answer
46 views

Drop partition scheme with orphan indexes

I have a partition scheme in my SQL Server database that I am trying to drop. This scheme was used by 2 indexes, which I deleted. I can't delete the scheme, since it appears to still be used by the ...
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1answer
59 views

Oracle DB - Is it possible to distribute data of a table onto multiple servers?

BigTable[1]-like systems (HBase[2] for instance) allows a table to be distributed transparently accross multiple servers. This works as follows: Each server perform the read/writes operations on ...
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1answer
20 views

whether to merge partitioned table with only partially overlapping columns

I opted for MonetDB for my static data, but this might be less of a MonetDB-specific question about features than about RDBMS (or just SQL) in general. I have data with a few "cross-sectional" ...
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1answer
241 views

Partition by year and sub-partition by month mysql

I have a database with a date column having datatype as date. I am using mysql 5.6 The table is expected to have 10k rows each day. I want to create partition on the table on year range and then sub ...
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1answer
77 views

How to get accurate row counts in partitions in a table

I am trying to fetch row counts in each partition for a table. But I got confused as in sys.partitions row counts is on basis of indexes. So how can I get exact row count for partitions in a table.
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1answer
85 views

Partitioning large mysql table

I have a large (40GB) table I would like to partition. The rows are essentially write once read many. Currently I am using mysql 5.5 innodb with file_per_table. It's tough to optimize this table since ...
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1answer
40 views

Does partitioning sometimes require denormalization?

Specific example of what I'm asking: Say that a SaaS app has an Order table with CustomerID and a child OrderItem table. We want to partition both tables and we want to use CustomerID as the ...
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41 views

dynamic sql: merge partitioned tables (annual tables into a single table of all years)

I need to merge (UNION) data from annual tables into one large table. I am confused about how dynamic SQL (or else) should be used for this. Below is an updated version of my question on ...
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36 views

MySQL 5.6 TO_DAYS partitioning schema always searching in first partition for queries which include <,> or BETWEEN operators in where clause

I have this table definition: CREATE TABLE ClientInfo ( IPAddr VARCHAR(16), RepDate DATETIME NOT NULL )ENGINE=MyISAM; PARTITION BY RANGE(TO_DAYS(RepDate)) (PARTITION pNULL VALUES LESS THAN ...
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1answer
29 views

How does partitioning and the lack of a primary key affect ON DUPLICATE KEY UPDATE

Consider a table with the following columns: phone BIGINT NOT NULL PRIMARY KEY, name VARCHAR(64), state VARCHAR(64) We would like to partition the table on state, however that would require ...
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3answers
121 views

Is table partitioning improving performance? Is it worth it?

I have just been involved in a project on which I will have to develop a data migration process and a web interface that uses an already existing SQL Server DB. This DB was developed by another person ...
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180 views

Sharding Postgres Database

I have a Postgres database that has grown to the size where it is no longer feasible to store everything on a single database node. There is a Customer table in my schema where each row represents a ...
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1answer
180 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 ...
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1answer
60 views

Partitioning a table state

So far I always used date ranges to partition my tables, however now I like to do it by state or a selected list of cities where all others that are not explicitly listed in an "other" partition, is ...
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1answer
83 views

Is searching an alternate index on a partitioned myISAM table concurrent or serial?

I have a myISAM table with 30 partitions. The primary key is a SHA1 hash value, which is also used in the partition selection function. I also have an alternate key - an autoincrement integer. Since ...
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1answer
62 views

What inefficiency does sharding & partitioning attempt to address? [closed]

I have never implemented sharding or partitioning, but from what I understand, multiple servers are used to distribute large amounts of data. Is this because of a limited hardware budget or to ...
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1answer
20 views

Logically Horizontale-Partitioned Tables

I have two legacy tables, lets call them TableA and TableB. Both of them fall under the same schema design with identical columns, in other words you can union them directly as one table. The only ...
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3answers
391 views

Best practices for configuring the Drive/Filegroup setup for Microsoft SQL 2008

I am a software developer for a small company. I wish we had a dba but not in the cards at this point for this company. I was working on migrating our 75gb SQL Server 2000 database to SQL Server 2008 ...
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2answers
214 views

Return ID from partitioned table in postgres?

When I insert a record I need to return the inserted id by RETURNING. The problem is that the table is partitioned and in partitioned table I can't use RETURNING. I run multiple queries at once so I'm ...
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1answer
61 views

Does Oracle Partition by Reference optimizes join queries

Oracle 11g has a new feature in partitioning tables called partition by reference. I want to know whether Oracle joins (nested-loop-joins or hash-join or ...) rows from proper partitions when joining ...
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1answer
52 views

Proper drive partitioning in Linux for Oracle

I have a current production physical server running on RHEL and I'm going to be building a new Oracle Linux VM to take it's place. Below is a listing of the existing physical drive partitions. Can ...
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138 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 ...
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2answers
421 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 ...
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398 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 ...
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1answer
112 views

Postgres: Put 1 database in separate HD partition?

I have 2 HD partitions - one with SSD and another with regular hard drives. I have multiple databases (as in logical database, not physical) with 1 data directory. I want the data for 1 of the ...
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1answer
1k views

Database partitioning - Horizontal and Vertical sharding - Difference between Normalization and Row Splitting?

I am trying to grasp the different concepts of Database Partitioning and this is what I understood of it: Horizontal Partitioning/Sharding: Splitting a table into different tables that will contain a ...
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1answer
131 views

Snapshotting Database Tables

I have a reporting database (in SQL Server) that takes nightly snapshots of the production data (Oracle) for users to query against for the next day, but now the requirement is getting to be that they ...
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1answer
59 views

Constrain exclusion to fetch latest N rows

I'm managing a table with several million records which are being inserted in real time. A part of my app needs to display the last N inserted records, so at the beginning I just queried for: ...
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162 views

PostgreSQL 9.2 - Partitioning: Constraint Exclusion on SELECT not kicking in [closed]

My partitioned table SELECT queries include all partitioned tables even though checks are in place and constraint_exclusion = on. The insert trigger works fine and new rows are inserted into the ...
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1answer
379 views

Partitioning MySQL vs PostgreSQL

For our new system we are looking for database server. We considered a lot of pros/cons for MySQL(InnoDB) vs PostgreSQL and the breaking point for us is partitioning. We will choose the one which ...
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2answers
2k views

Oracle: adding subpartitions to existing partitioned table

In Oracle 11g, is there a way to introduce subpartitions into an existing partitioned table? I cannot seem to find a combination of EXCHANGE and SPLIT partition that does the right thing. SPLIT will ...
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1answer
191 views

Large difference in disk space used by partitions

I have a partitioned table that contains about 155 million records total. It's partitioned by year and the partitions for both the current and previous years contain about 25 million records each. ...
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205 views

Should I group by and then join, or join and then group by?

(oracle's optimizer does the same thing for both approaches when just two tables are involved, thus my question involves three tables) Assume three tables t1, t2 and t3 with a pairwise 1:n ...
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198 views

Is database partitioning for performance reasons meaningful in virtualized environment? [closed]

When running SQL Server on real hardware partitioning database and placing different partitions with different tables on different hard drives can be beneficial for query performance. Or, to simplify ...
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1answer
306 views

Bulk loading to partitioned table

I am designing a database application which will be using PostgreSQL 9.3. My question is regarding bulk loading a CSV to a partitioned table. I have done a lot of research, but I'm still unsure of ...
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68 views

MySQL: Optimizing for large but discrete data sets

In brief: I'm developing a database that handles GTFS datasets from multiple transit agencies. Each dataset contains millions of rows in the stop_times.txt file (and thus its corresponding table). ...
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56 views

Best way set clustered primary key on a partitioned table?

I have the following table. create table T (K1 date, K2 int, K3 varchar(10), C1 int, C2....) The table will be partitioned by K1 (K1 has low selective. the data will be appended in the order by ...
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How to move partitions between filesystems

We have ~9TB MySQL database which consists from a few tables which are partitioned by day. Sum of daily information is ~20GB. Database is practically write only. There are at most tens of queries ...
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79 views

Mysql, sql server, oracle tables get too large [closed]

I hear a lot about things that, it is a lot cheaper to buy new harddisk than pay staff to come up with genius ideas how to save resources. But what I don't understand, is how these databases handle a ...
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56 views

How do I debug an Oracle Linux Diskspace Issue?

I have about 429GB Diskspace allocated to this VM. I see that only 179GB is being used. Now when I try to add a 128GB file I get an I/O error saying I do not have any space left. I need to be able ...