2
votes
1answer
2k views

creating PKs for existing tables - altering column constraints

I am quite new to DB2, so I googled around how to ask questions correctly and so I hope I can provide all necessary information. I have an existing table A1230922.CALSONW with several (195) columns ...
0
votes
1answer
2k views

Connect to Mongo Shell on OpenShift

I have a gear running a instance of mongoDB. I wish to connect to the mongo shell. How can I do it? I have rhc and mongoDB installed on my computer. I have RockMongo on the gear, but I cannot create ...
0
votes
1answer
7k views

How index work in oracle? [duplicate]

I want to understand : How index work in oracle. How they are stored in the disk. How they increase the efficiency of a query? By third point I means how Index contribute to the efficiency of ...
0
votes
0answers
41 views

Changed password on Postgres but I still can log in with the old one [closed]

I changed my password via alter user, but can still log in with the old one. In the 9.1.6 version of postgresql I resolved this problem by killing all the processes through pg_terminate_backend, but ...
2
votes
0answers
135 views

WMI event alerts

I am trying to understand WMI event alerts and have implemented a mirror with alerts on DATABASE_MIRRORING_STATE_CHANGE such that all database failover if the state is either 7 or 8 (manual failover ...
1
vote
1answer
102 views

Designing a fragmentation database? [closed]

I did some research about distributed databases, but I still have some questions. I understand there is something called "fragmentation database" but I can't find any help full document for ...
-1
votes
2answers
889 views

MySQL: how to copy a database from one server to another without export / import

I have access on two different Windows systems. There is one MySQL database on one system which I want to copy to another system. Please note that I haven't username and password for DB access on the ...
0
votes
1answer
53 views

MongoDB Balancer:move data inside replication set or across replication set?

After reading the document of mongodb on the balancer topic , I have two questions: 1.If I set Balancer on , will the db operation efficiency will be influenced ? 2.Still ,I cannot understand ...
4
votes
1answer
752 views

2 B-tree indices OR 1 GiST index on tsrange — which will perform better?

I have a table which is storing reservation data using the columns starts_at & ends_at Whenever I'm querying the table to find overlapping reservations, I have an option of using one of the ...
0
votes
2answers
445 views

Separating a date column in Access into Month, Day and Year while keeping the new columns ordered by a seperate column(primary key)

I have a column titled DateOpen which lists the date files were opened in d/m/yyyy format. I want to split the entries in that column into new columns titled MonthOpen, DayOpen and YearOpen while ...
1
vote
2answers
1k views

MySQL replication: slave not updated

This has been asked many times over but we really cannot get a simple Master-Slave Mysql (5.5.25) replication to work for our two dbs (FatTree and Torus). And no trace of error in the logs. The ...
0
votes
1answer
776 views

DB2 - Archive mode - large number of logs in logarchmeth1 folder

maybe for someone this is begginner's questions. I read lot of documentation and set: `LOGPRIMARY 6 LOGSECOND 4 LOGFILSIZ 4096 logarchmeth1 Disk - C:\archive logpath C:\active` Number of logs ...
5
votes
2answers
31k views

How can I dynamically alias columns?

I have a table (not designed by me) which has 20 variably named columns. That is, depending on what type of record you are looking at, the applicable name of the column can change. The possible ...
2
votes
1answer
50 views

Do shorter names exist for “one-to-many”, “one-to-one”, “many-to-many” relationships?

In terms of generic variable naming or even everyday geek discussion, do shorter and "cleaner" terms exist for one-to-one, one-to-many, and many-to-many relationships. For example, in discussion of ...
3
votes
1answer
645 views

Most efficient queries on flags in TSQL: bit field or table join?

Looking for the most efficient database structure for selecting rows from a large table based on one or more true/false values. For example, whether or not a user has opted in to marketing ...
0
votes
1answer
108 views

SQL Server database recovery

By mistake one of my colleague in the office has restored .mdf and .ldf files of another database to production with existing database name. So existing database was overwritten with new backup. Is ...
0
votes
2answers
150 views

How to store a database table in multiple disks with assigned ratio?

I am going to deploy database tables to multiple disks. My database layout would be like following example: There are 3 tables (Customer, Order, Product) and 4 disks (disk_A, B, C, D). Customer: 5% ...
3
votes
1answer
553 views

With SQL transactional replication, does changing user permissions to a table trigger a new snapshot?

I was hoping to get some help with a SQL Server 2012 transactional replication scenario - or maybe just my understanding of where permissions are stored in SQL server. If I change a users permissions ...
1
vote
2answers
534 views

Elasticsearch: Versioning a document on revisions

I currently have a document which gets revised regularly, I want to keep track of the document by keeping each old version of the document. So if document A has a summary and update date I want to, ...
5
votes
4answers
19k views

Changing IP address of SQL Server 2008 R2

I would like to know if there are any dangers or relevant precautions before changing the IP address of a SQL Server 2008 R2 box. We have built a virtual PC with Windows Server 2008 R2 and SQL Server ...
1
vote
1answer
583 views

Error while importing sql - Specified key was too long; max key length is 1000 bytes

I am trying to import an sql file which shows me the following error: Error SQL query: -- -------------------------------------------------------- -- -- Table structure for table `users` -- CREATE ...
3
votes
0answers
116 views

SQL Server replication - recommendations for stability

We have two SQL Server 2008R2 Standard servers, and we've set up replication of a single database between them. The replication is about as simple as it can get - it's a transactional replication from ...
0
votes
1answer
496 views

Installing Oracle 11g on Windows SBS 2011 64 bit

In the Oracle web site, I found the following requirements: http://docs.oracle.com/cd/B28359_01/install.111/b32006/reqs.htm#CHDHGGFE Oracle Database for x64 Windows is supported on the following ...
4
votes
2answers
529 views

MySQL query returns unexpected results inside a stored procedure

This is my stored procedure: CREATE DEFINER=`root`@`localhost` PROCEDURE `isUserValid`(IN `facebookId` VARCHAR(20), IN `userAccessToken` TEXT) NO SQL COMMENT 'check if user is valid. return ...
1
vote
1answer
16k views

query to search a particular word/string in toad/oracle

I trying to find out a word/string named 'audapro_ind' in oracle database in toad. This word can be present anywhere in column of table, function, procedure etc. in oracle database I tried few ...
3
votes
2answers
9k views

Best practice to avoid a composite key?

Suppose my students fill every year a survey, containing some questions (called fields) which answer is real-valued (called value). Every student may answer the survey, at most once a year. A simple ...
0
votes
1answer
42 views

Continuous jobs on Redis [closed]

I want to setup a script that sums up a bunch of values in a list and then puts down the result in total-count and then removes the entire list, And this all should be repeated once a minute or as ...
1
vote
2answers
3k views

How to know spid which is filling tempdb from temp table name in sybase

I received alert that tempdb is going to be full and temp table name aslo provided. Now I want to know how to check which spid is filling tempdb from temp tablename.
0
votes
2answers
70 views

Full Transaction Log on closed source system [duplicate]

I have a closed source application which has the transaction log filling up on a daily basis to 60+gigs. I have ran a trace on the database and no inserts and updates are occurring. The following ...
10
votes
3answers
6k views

What is a valid use case for using TIMESTAMP WITHOUT TIME ZONE

There is a long and quite elucidating answer on the differences between TIMESTAMP WITH TIME ZONE -vs- TIMESTAMP WITHOUT TIME ZONE available in this SO post. What I would like to know is: are there ...
1
vote
1answer
263 views

Using “Generate Scripts” with EMERGENCY/SINGLE USER mode

I am trying to create an INSERT script to salvage data from a single table in a corrupt database. I've succesfully put the database online and put it in EMERGENCY / SINGLE USER mode (following this ...
1
vote
1answer
141 views

How to relate 2 user profile tables to a single login table?

I have an Employee table , and another table named Student. Now I have a third table named the Login. Employee has emp_id as PK , and other specific attributes for an employee. Student has std_id as ...
1
vote
3answers
834 views

MySQL “lost” all data(InnoBD)

Today I was making some work with site and I get error what MySQL can't rename file (to make changes in BD). Next I tried to restart MySQL, and it failed to stop MySQL. Then I did go to /var/lib/mysql ...
-1
votes
1answer
43 views

Grouped Data tracking [closed]

I have a MS Access Database that tracks clients, client regions and transaction types. Users are keying in transactions and once done, the system needs to create letters to the client regions ...
1
vote
1answer
1k views

DB2 - Archive Mode - on what values to set LOGPRIMARY,LOGSECOND,LOGFILSIZ?

we must set our database from CIRCULAR to ARCHIVE mode in order to enable ONLINE backups. Backups will be done every 1 day. Database is now almost 30GB. Database grows approximately 1GB per month. ...
4
votes
2answers
419 views

What is the fastest way to fetch the last row from a table?

I have a PostgresSQL table, Prices, with the columns: price (Decimal) product_id (Int) Prices get updated regularly and I keep old prices in the table. For a given product, the last price in the ...
5
votes
1answer
58 views

Is it possible to decouple row size estimation from maximum column width?

In other words, is it possible to declare a column VARCHAR(n) and have the estimated size be something other than n/2? An example use-case might be storing URLs - you expect most to be relative and ...
6
votes
1answer
696 views

MyISAM with Innodb in the same Wordpress database reduce performace?

My new Wordpress database all the Wordpress created tables use InnoDB engine and plugin created table use MyISAM. But older site database all the tables use MyISAM table engine. I use MySQL 5.5.35-...
1
vote
1answer
1k views

INSERT take too much time

I have in my MySQL DB a few tables Most of the time, I'm only doing INSERT in my db. I have up to 4 connections to the DB, each one inserting into a different table. There cannot be two connections ...
3
votes
1answer
80 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 ...
0
votes
1answer
432 views

Where can I get best resources to learn sql? [duplicate]

I am very new to the databases just have basic knowledge about it. I want to learn sql language and dont know where to start. Please help me to start with it. And what is the difference between ...
1
vote
2answers
132 views

Backup architecture for frequent backups of business critical DB

We've got a database (mysql) driven application which contains business critical information, were looking at building a system that will allow us to backup the db frequently (every 15 minutes, ...
1
vote
1answer
196 views

Mongo db and sharding / replica sets concept questions

I have few questions about sharding and replica sets: I am planning to write important logs to a sharded environment. about 100 million rows in a day, If I will connect to a single MONGOS process , ...
1
vote
2answers
62 views

Multiple “model” DBs — or db creation 'profiles'

I know you can't actually have multiple 'model' DBs on the same server instance. BUT, I'd like to have something almost like it. Basically, we have a business model where each customer is its own DB, ...
5
votes
1answer
192 views

redundant foreign keys in PostgreSQL - are there any indexing benefits?

Note: this is not the same as this SO question which is about adding redundant information in the tables themselves. Does the final statement in the below series of statements buy me anything in ...
3
votes
1answer
366 views

Enforcing constraints “two tables away”

I ran into some trouble modeling an electrical schematic in SQL. The structure I'd like to capture is part ←────────── pin ↑ ↑ part_inst ←───── pin_inst where "inst" is short ...
1
vote
1answer
67 views

What problem prevents well defined behavior of a foreign key on a non-unique column?

In my noob opinion, it strikes me that in a serialized environment, this shouldn't be a problem. Is that correct? If not, please explain to me why a foreign key's behavior on a non-unique column is ...
0
votes
2answers
1k views

Configure postgresql recovery again to be slave

I completed a replication setup using PostgreSQL. Everything was working fine, so I proceeded doing a test by bringing down the main database and promoting the slave to be new master (via touch ...
4
votes
0answers
325 views

User locking tables without privileges [closed]

This is a restatement of a question asked on the GIS Stack Exchange here. Although it has GIS-specific elements it may be be a more general PostgreSQL effect. I have a PostgreSQL 8.4.4 database ...
1
vote
1answer
2k views

MONGODB primary became secondary after servers restart

I had this config before restart: { "_id" : "rs0", "version" : 5, "members" : [ { "_id" : 0, "host" : "Ubuntu12041vanilla:27017" }, { ...

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