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

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2
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1answer
51 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 ...
0
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0answers
19 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 ...
0
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1answer
34 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?
3
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1answer
59 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 ...
1
vote
1answer
84 views

What is a “leaf expression”?

What is a "leaf expression"? Partition-clause expressions are limited in the following ways: Your partition-clause must calculate a single non-null value for each row. You can reference multiple ...
0
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1answer
64 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 ...
0
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1answer
92 views

How to split the Wordpress database?

FYI - I originally posted this question under the Wordpress Development site here: http://wordpress.stackexchange.com/questions/145861/how-to-split-the-wordpress-database I have a site that is used ...
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0answers
71 views

Greenplum's poor dynamic partition elimination

I have large fact tables in Greenplum with many years of history that are partitioned by a surrogate key (which represents time). Of course almost all queries are for recent time periods where the ...
0
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1answer
22 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" ...
0
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1answer
276 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.
0
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1answer
49 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 ...
0
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0answers
55 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 ...
0
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0answers
41 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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2answers
515 views

Strange behaviour with MySQL 5.1 TO_DAYS partitioning schema

I have this table definition: CREATE TABLE `va_ventas` ( `ID` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, `Date` DATE NOT NULL, `Time` TIME NULL DEFAULT NULL, `Country` VARCHAR(3) NULL DEFAULT NULL, ...
0
votes
1answer
34 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 ...
2
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2answers
355 views

Creating a partition on my soft-delete indicator column

In SQL Server 2008 R2 I am exploring the use of partitioning tables. We have a soft-delete scheme which is sometimes an IsDeleted bit NOT NULL and sometimes a DateDeleted date NULL I want to focus ...
0
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1answer
2k 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 ...
0
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3answers
208 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 ...
13
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3answers
2k 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 ...
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0answers
662 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 ...
1
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2answers
62 views

Oracle tables partition related

Here is my doubt. Is it possible to apply a partition to one table depending in the partitions values of another one? Why I am asking? I have one table where information headers are persisted, and ...
3
votes
1answer
1k views

How to take partitions or filegroups out of service

I'm an experienced SQL Server DBA but new to partitioning, and I have a couple of questions. Using SQL Server 2008 R2 Enterprise Edition. I've inherited a large customer metrics database that grows ...
1
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1answer
65 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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2answers
85 views

What are the possible risks involved in partitioning large database tables? [closed]

There has been much talk about the benefits of table partitioning in Relational DBMS. I would like to know: Are there any risks to table partitioning ? What measures are there to take to minimize ...
3
votes
1answer
67 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 ...
5
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0answers
196 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 ...
3
votes
3answers
700 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 ...
1
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1answer
21 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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2answers
277 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 ...
0
votes
1answer
100 views

What is the best partition technique for large table with TEXT column?

MySQL: What is the best partition technique for large InnoDB table (around 1.5M rows) with TEXT type of column? There is a FULLTEXT index on the TEXT column, which is very essential for my searching ...
2
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1answer
135 views

Availability Groups and Partition Swapping

Is it possible to use SQL 2012 Availability Groups over two machines and perform partition swapping on the primary machine ?
0
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1answer
69 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 ...
0
votes
1answer
55 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 ...
4
votes
2answers
277 views

Strategy to deal with multi billion row simulation results and partitioning

I am trying to come up with a good way to deal withthe results of statistical simulations from a dba point of view. We generate about 500 million rows per day, most of which are "garbage" (i.e. the ...
6
votes
3answers
18k 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?
0
votes
1answer
378 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 ...
5
votes
2answers
526 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 ...
4
votes
2answers
840 views

Partitioning a table vs moving entries to another table

I don't understand how partitioning helps me more or less than using a separate table to store older records. I need to maintain a list of stock entries along with historical records about the stock. ...
3
votes
1answer
1k views

How to structure Master/Detail tables for performance without denormalizing?

Some Background Info We have a set of tables that holds all the transactions for our system, TransactionHeaders and TransactionDetails. There are roughly 80k Transactions a day which translates to ...
3
votes
2answers
2k views

ALTER TABLE SWITCH statement failed

ALTER TABLE SWITCH statement failed because column does not have the same ANSI trimming semantics in tables... Does anyone knows how to fix that on already existing table full of data? Well, I've ...
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1answer
1k views

Indexing issues while partitioning with dbms_redefinition

I get an error while doing the redefinition. Following are the steps which I have taken so far: Step 1. Start redefinition DBMS_REDEFINITION.CAN_REDEF_TABLE(v_name, 'T_FDC_TOOLCONTEXT', ...
6
votes
1answer
545 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 ...
2
votes
1answer
3k views

Rename interval partitioning system generated partition names

I have an existing table which I partitioned (interval partitioning on a daily basis) using dbms_redefnition. PARTITION BY RANGE ("TIME_ID") INTERVAL (NUMTODSINTERVAL(1,'DAY')) (PARTITION "p1_1" ...
1
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1answer
169 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 ...
0
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1answer
67 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: ...
0
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1answer
361 views

MySQL Read Speed and Partitioning on Separate Drives

Introduction Simple project but for an heavy read load -90% reads- over a table(~20Milion Rows ever-growing where I have to boost performance and ensure response low time for read queries) that was ...
3
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0answers
194 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 ...
4
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1answer
227 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. ...
3
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0answers
221 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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2answers
227 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 ...