0
votes
1answer
6 views

How should I index a UUID in Postgres?

I'm new to PostgreSQL and somewhat new to databases in general. Is there an established way of how we should index UUIDs in Postgres? I'm split between using hashing and using a trie, unless there's ...
0
votes
1answer
10 views

Can you enforce uniqueness in MySQL based on column in foreign table?

I am refactoring one of my database tables and I've come up with an issue. Specifically, I have a table with four columns. We'll call the first three my.a, my.b and my.c. I have a uniqueness ...
1
vote
1answer
43 views

Do I need a database license for my application?

I am developing an application for cemetery management. It is my first "big" project, so I'm not familiar with the "corporative" side of this. First, some info about the app: Has 3 local database ...
0
votes
0answers
6 views

MYSQL - number of rows returned equals number of connections?

Does my query get sent to the database once and I get a list of all the results in one shot which I then loop through, or do I have to request the next row from the DB each time? Essentially, does ...
-1
votes
0answers
23 views

Why did windows “repair” delete my database tables?

When I ran windows "repair" it deleted some database tables. Is it possible to quickly restore the tables when I don't have a backup as it's my testing server as windows deleted them? It is now only ...
0
votes
0answers
25 views

sys.sp_reset_connection. Why theres a lot of them ?

Theres a lot of questions here on DBA EXCHANGE. But none of them can help me. I have 2 problems: 1) Using sp_whoisactive, I found lots of sys.sp_reset_connection;1( I know they are ...
0
votes
0answers
28 views

DBA vs DB Engineer vs DB Programmer [on hold]

What are the specific differences between a Database Administrator, Database Engineer, and a Database Programmer. I'm trying to determine which title is truly most fitting for my day to day duties, ...
0
votes
1answer
46 views

Can we create indexes on views in SQL Server? [on hold]

Can we create Indexes on a view in SQL Server 2008? I have heard about indexed view, which can give performance improvement, but the problem is data refresh on those views: Can it be auto updated, ...
0
votes
1answer
22 views

MySQL command “SHOW DATABASES” returns invalid databases

I have a MySQL server with a number of databases on it - 16 if I'm not mistaken. When I run the SHOW DATABASES command I get 30 rows. I would have expected 17 rows: The 16 databases and ...
1
vote
2answers
45 views

How to order by alphanumeric codes in SQL Server

I have a table with some project codes. These codes are e.g.: B001, B002, Z15001, Z14001, P003,... I need this result table: Z15001 Z15002 ... B001 B002 ... C001 C002 ... Z14099 Z14098 Z14097 ... ...
0
votes
1answer
9 views

SQL Server Mirroring (with Witness) and Client Timeouts

Can you explain what happens in this situation. Imagine I have a Sql Server Mirroring set-up with 2 databases and 1 witness. Database clients have in their ConnectionStrings the Principal= and ...
0
votes
0answers
19 views

Data Mock up for my table

I want to mock up data for a table. So I need to generate a million sample records for the table? Table structure is like this: CREATE TABLE Employees( EmployeeID int NOT NULL, FirstName ...
0
votes
0answers
24 views

Ongoing Administration comparison PostgreSQL vs Firebird [on hold]

I am trying to decide between these 2 database systems for a project. I have frequently read that Firebird requires practically no ongoing administration once it's set up. Does PostgreSQL require ...
-1
votes
0answers
22 views

Creating Mview in Oracle is throwing error

I keep on getting error when I try to create a fast refresh materialized view. Not sure what is the cause of getting the error. ---PREBUILT TABLE--- Create table k_dim_mvw( id NUMBER(10), time ...
0
votes
0answers
13 views

Excel connecting to SQL Server Database and editing tables [on hold]

I would need to connect from within Excel to a SQl Server table and to be able to edit and update the table rows using that excel. Is there a simple way of doing this without having to write ...
1
vote
1answer
20 views

MySQL Index Creation Internals

Right now there are two ways to build an index of a table in MySQL: Create the table structure first, then import the data and add indexes later. Create the table structure with indexes and then ...
0
votes
1answer
17 views

How to remove data from multiple tables with different foreign keys without using ON DELETE CASCADE?

I have the following SELECT statement: SELECT * FROM "Users" u INNER JOIN "Calendars" c ON (u."UserId" = c."UserId") INNER JOIN "Actions" a ON (c."CalendarId" = a."Calendar_CalendarId") WHERE ...
1
vote
0answers
26 views

MySQL bulk deletions

I am currently looking at how to most efficiently delete rows from a table in bulk. The database I'm using is MySQL with innodb. The table I want to delete from can be any size, but will usually be ...
0
votes
0answers
5 views

Cassandra - save file

I'm new with Cassandra, and even more - I never have such task for habitual RDMS systems, like MariaDB or Oracle. So, how can I store file in to Cassandra's table? Preferably using Python-driver, but ...
5
votes
1answer
281 views

Why is SELECT * much faster than selecting all columns by name?

On a table with columns a,b,c,d,e,f,g,h,i,j,k I get: select * from misty order by a limit 25; Time: 302.068 ms And: select c,b,j,k,a,d,i,g,f,e,h from misty order by a limit 25; Time: 1258.451 ms ...
0
votes
1answer
12 views

Cannot overwrite file: /var/lib/mysql/ibdata1 when using Percona xtrabackup

I am receiving an error when I am trying to restore from a percona backup to my local mysql server. Cannot overwrite file: /var/lib/mysql/ibdata1 at /usr/bin/innobackupex line 2128. sudo ...
-3
votes
0answers
20 views

best software to run Oracle code [on hold]

what kind of software is best to download on PC with Windows OS to practice in writing and running code in Oracle (let's say at school or for preparing for certification)?
1
vote
0answers
15 views

Certification Test 70-461 [on hold]

I am a student at University of Houston-Downtown and looking to take the Database Administrator certification test sometime in October. I am hoping that someone has been recently been certified or ...
1
vote
0answers
7 views

'sp_releaseschemalock' causing me a blocking issue?

why 'sp_releaseschemalock' causing me a blocking issue? what proccess that must execute sp_releaseschemalock or what function of sp_releaseschemalock? I have searched various forums or blogs about ...
1
vote
0answers
12 views

Postgres not using the index even when rows returned is 5% of the table

I have a postgres table with the following structure: +---------+-------------+-------------+----------+---------+---------+ | id | timestamp | numvalues | text1 | text2 | text3 | ...
0
votes
0answers
17 views

Got an error from unknown thread, /pb2/build/sb_0-13157587-1410170252.03/rpm/BUILD/mysql-5.5.40/mysql-5.5.40/storage/myisam/mi_write.c:226

I am using mysql 5.5.40-log and my default storage engine is Innodb, I found this error in my error log "[ERROR] Got an error from unknown thread, ...
1
vote
1answer
37 views

Why does MS SQL Server return a result for empty string check when Unicode string is not empty

select * from (select N'ግዜ ' as t) as t2 where t= '' the string 'ግዜ ' matches the above check, why is this?
0
votes
0answers
9 views

Database design question for sorta rookies [on hold]

Are there any books or Github examples of how to design a database for use with an android app. Specifically the user will be logging into the app via mobile device or Web browser. I imagine aside ...
0
votes
0answers
8 views

how to do a backup and restore for a single database with mysql enterprise backup

I am Chinese, the documentation of mysql enterprise backup is hard to understand for me, and now I need to finish my job quickly, I wonder is that possible to backup a single database and restore it ...
-1
votes
2answers
10 views

psql: could not connect to server and socket /var/run/postgresql/.s.PGSQL.5432

I have installed postgresql 9.4 and I removed postgresql 9.3 from my computer. Now when I try to run: foo@bar:~$ psql I get the error psql: could not connect to server: No such file or directory ...
0
votes
1answer
10 views

SQL Server Express 2012 Repair

I have a copy of SQL server Express 2012 database which may be corrupt. When I tried to run a repair on it I was asked for the original installation media. The Options were for an MSI or ISO image. ...
0
votes
0answers
5 views

Unable to import database through osm2pgrouting

I am very frustrated by the following errors while trying to import NewDelhi by osm2pgrouting tool: osm2pgrouting -file "/home/user/Downloads/new-delhi_india.osm" -conf ...
0
votes
0answers
5 views

Cannot access MS Access DB with non-Admin users

I have created several users in a MS Access database using "User-Level Security Wizard" in Access 2013. The problem: I am only able to log in with users belonging to Admins group. Other users ...
0
votes
0answers
12 views

could not open log file “/var/log/postgresql-2015-05-24_181212.log”: Permission denied

I installed postgresql from source on Ubuntu 14.04 (I also installed from repositories too before, I just want to get a feel for both of them right now, as I will heavily rely on this database). So ...
0
votes
0answers
11 views

How to create a procedure by using the existing procedure in oracle 11g? [on hold]

Can anyone please tell me? How to create a procedure by using the existing procedure? ( SQL DEVELOPER ) Thanks! Arunkumar.
0
votes
0answers
15 views

MySQL Cluster - Adding more storage space

I have spent a few days looking into different MySQL Cluster options, such as Percona and MariaDB Galera, however from what I understand neither of them can do what I would like it to do. What I am ...
0
votes
1answer
21 views

Multiple database directories with postgresql

I installed postgresql from source on Ubuntu 14.0.4. It is located in /usr/local/pgsql. At first, I created a data directory at /usr/local/pgsql/data and then ran initdb -D /usr/local/pgsql/data I ...
0
votes
1answer
19 views

JDBC local MSSQL Server connection string

I have installed open source database management tool "dbeaver" and want to use it instead of Sql Server Management Studio. But there is a problem. I searched from the internet but somehow I could not ...
3
votes
1answer
54 views

How to check foreign keys related to a table

How to see foreign keys related to a table in MySql? Background : I wanted to drop a table in MySql which has a foreign key constraint. When I do it I get this: Error Code: 1217. Cannot delete or ...
-1
votes
2answers
26 views

Double entry bookkeeping database design

I'm doing an accounting software and I need to enforce double entry bookkeeping system and I have the classical problem of 1 row per transaction versus 2 rows. Lets take an example and see how it ...
2
votes
1answer
36 views

How to archive a whole database?

I have a database that is not going to be used anymore but that needs to be kept around for a long time. I'd like to remove it from the production system. My goal is to save storage space when ...
1
vote
1answer
52 views

When Should You Shrink Your Database

I have read conflicting articles about shrinking a databases. Basically, our database grew 100% overnight from 150 gigs to 300 gigs b/c I believe it was with staging tables I put in. However, all the ...
0
votes
0answers
12 views

hashed password retrieval in mysql

here I am again with the next question! I hash a password as follows: mysalt=os.urandom(12).encode('hex') passhash =mysalt + pw hash =str( pbkdf2_sha256.encrypt(passhash)) How can I verify this ...
0
votes
0answers
15 views

SQL Server hangs during backup on EC2

Once and then our SQL Server will "hang" during its weekly full backup. When this happens, external connections start to timeout. The symptoms are: Connections timeout The sqlservr.exe process sits ...
0
votes
0answers
10 views

What could cause 300+ connections from a simple query in MySQL?

I am retrieving results from a table in MySQL 5.5. When I run even a basic query on this table hundreds of connections are shown in the Server Status screen in MySQL Workbench. Even for a simple query ...
1
vote
0answers
23 views

Uninstalling MS sql server 2012 issues

I'm trying to uninstall ms sql server 2012. But when I click Microsoft SQL Server 2012(64 bit) and choose remove option it shows like this. Then how can I remove the MS SQL Server 2012? Please help. ...
0
votes
0answers
5 views

Post categories model for a user submission wedbsite

I'm building an user submission site where users can make posts to content_types: Blog, Movies, Photos, Forums. Since these content types only have slight variances I would like to keep them in one ...
1
vote
1answer
25 views

Oracle: Recover source code/table structures from “utterly wiped out” development database

Given an Oracle 11.1 database used for development, running in NOARCHIVELOG mode, where all datafiles (including undo) have been wiped out; and only SYSTEM and SYSAUX datafiles and control file remain ...
1
vote
1answer
110 views

Dealing with Difficult DBAs [on hold]

At one point, test database deployments within my department were handled directly by the database developers. The typical process was that the developer would unit test their changes in the ...
0
votes
0answers
16 views

Filesort when using view

I am sorry for asking, but I can't figure what i am doing wrong and filesort appears in my explain. The id column that I use for sorting in the following examples is a primary key... If I create ...

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