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votes
5answers
14k views

MySQL said “InnoDB: Initializing buffer pool, size = 128.0M”, does it mean it is using 128MB RAM?

I am just using a very few InnoDB tables (e.g. less than 1MB), but during MySQL startup, it said InnoDB: Initializing buffer pool, size = 128.0M Does it mean even I am using in such a small size, ...
4
votes
4answers
594 views

DB Optimization with 2 to the power of N - Approach clarification

This is a request for analysis and better performance approaches, one of my colleague has come up with an approach in optimizing the DB and it looks very impressive too. Can someone please let us know ...
1
vote
1answer
238 views

MySQL detect duplicate human names [closed]

I've been tasked with identifying a solution to help identify possible duplicates when inserting new user records into a MySQL database. Does anyone know of any cheap, preferably free, solutions? The ...
3
votes
1answer
24k views

Multiple left joins or subquery?

I'm working on joining multiple tables together to extract some data related to user "runs", this includes basics like runID, username etc but also joins to the run times and favourites. I have the ...
0
votes
1answer
1k views

Print filter parameters on a report

I'm using MS Access 2010. I have a form with a number of fields of various types (number, text, lookup, checkbox). Users can right click on any field to filter the form. Then I have a button that ...
1
vote
2answers
3k views

Join three tables

I have those three tables SELECT occuId as 'Occupation Id',occuDscr as 'Occupation Description' FROM occupation_field; +---------------+------------------------+ | Occupation Id | Occupation ...
0
votes
1answer
386 views

Does SQL Server full restore set the differential base?

Differential backups are taken as the difference between the current state, and the last full backup called the "differential base". Does restoring a full backup reset the differential base? If so, ...
7
votes
2answers
8k views

How to convert control characters in MySQL from latin1 to UTF-8?

While converting a database to UTF-8 I noticed a strange behavior regarding the control characters 0x80-0x9F. For example, 0x92 (right apostrophe) would not get converted to UTF-8 and truncate the ...
2
votes
1answer
284 views

sys.syshobtcolumns Help

Does anyone have a good link to documentation regarding how the syshobtcolumns and syshobt system tables are populated. The reason for asking is that we are receiving pagelatch_sh and pageliolatch_ex ...
1
vote
2answers
791 views

Microsoft SQL 2008 Cluster with replication

i am in the process of setting upi a SQl Server 2008 64 bit Failover cluster. A lot of the database queries that we are running during the days are db intensive and lock a lot of the tables while ...
3
votes
1answer
2k views

Calculate percentage of false records to total records within a aggregate function

I'm looking for a solution to calculate a percentage rate of a boolean value: Model: Products 1 <-> n Components Components.essential is a boolean attribute What I want to calculate ...
1
vote
1answer
6k views

unknown SET option beginning “oracle_sid…”

SQL> set oracle_sid=sid SP2-0735: unknown SET option beginning "oracle_sid..." SQL> emctl start dbconsole; SP2-0734: unknown command beginning "emctl star..." - rest of line ignored. SQL> set ...
4
votes
1answer
9k views

Converting Microsoft SQL Server collation to UTF 8

I've a Rails-Application, which reads data from a Microsoft SQL Server 2008 R2 Database. All umlauts are represented by a '?', so I checked the encoding of the database. The encoding is 'Latin 1'. ...
5
votes
2answers
13k views

Database logon trigger

To block a particular user and IP combination on an Oracle Database , I created the following trigger, and compiled without errors. Create or replace trigger you_may_not_login after logon on database ...
25
votes
5answers
67k views

PostgreSQL: How to create full copy of database schema in same database?

How I can copy my public schema into the same database with full table structure, data, functions, fk, pk and etc. My version of Postgres is 8.4 P.S. I need to copy schema NOT database
2
votes
2answers
701 views

Alternatives to sp_indexoption for Row Locks and Page Locks in SQL Server 2008

Are there better alternatives to setting the Row Locks and Page Locks in SQL Server 2008? The case here is to set the row and page locks to false on the table. The lock is in effect during a series ...
2
votes
1answer
530 views

Query takes hours

Up until now all queries in my PostgreSQL application were fast. During the last days, sometimes a query takes several hours. Index are healthy, because after dump, restore, vacuum -z, it is still the ...
1
vote
2answers
2k views

SQL Server 2008 R2 - user disk quota

Is it possible to apply restrictions on how much data a user / login may store in a database? I found no way to apply such restrictions to schemas, for instance. If there is no built-in mechanism ...
2
votes
2answers
1k views

Unable to locate database.mdf in production server

1) I want to attach a database from my development server to my production server. The database ESpiceHerbs from my development server is located at: C:\Program Files\Microsoft SQL Server\MSSQL10_50....
2
votes
3answers
3k views

Inventory Database Design Issue

I own a jewelry retail store alongside an online store, and am in the midst of building a completely custom system to track all of my inventory. I also have a number of stockists (other stores) that ...
4
votes
1answer
5k views

How Can I Correctly Pass a Table to a Stored Procedure in Oracle in SQL Plus?

Being new to Oracle, I'm almost certain I'm missing something simple here. This is what I'm trying to run: declare type string_table IS TABLE OF VARCHAR2(512); outuser nvarchar2(512); outrole ...
1
vote
1answer
2k views

In Oracle, what grants do I need as a non-schema user to view rows in all_objects?

I have two instances of an oracle 11g database, both have the same object definitions in the schema: tables with indexes and constraints, a sequence, and a stored procedure. The facts of the case: ...
4
votes
1answer
480 views

database design issue

This is my first time on this beautiful content rich site. I have a sql server 2008 database, but am not too experienced with good relational database design. My project is this: I have a school ...
20
votes
1answer
2k views

What's the anatomy of a columnstore index?

One of the new features in SQL Server 2012 codenamed Denali is the Columnstore index. I know a good bit about regular old row-store indexes, like the b-tree structure, differences in storage between ...
3
votes
2answers
145 views

How do I pull a backup of an oracle database so I can send it to a vendor

First of all, I know squat about Oracle databases. A vendor who is looking at converting our data from an older piece of software with an Oracle DB back-end wants a dump of our database to see what ...
1
vote
3answers
155 views

If A is next to B, how to automatically assert that B is next to A

I am working in Access 2010. Let's say I have a database that tracks where packages sit in a warehouse. Table: Packages PackageID (PK) PackageHeight PackageWidth PackageWeight PackageOwner (etc) ...
11
votes
2answers
6k views

Any gotchas at all with converting from MyISAM to InnoDB?

I'm ready to move from MyISAM to InnoDB but wanted to know if there was a full list of things to look for? For example, I haven't seen any list mention that running DISABLE KEYS on an InnoDB table ...
23
votes
1answer
15k views

Are there any risks to granting users SQL Server SHOWPLAN permission?

I'm doing some performance tuning on a large SQL server 2008 database, and the IT group is unwilling to give SHOWPLAN permission. In the past, "Show Execution Plan" has been the most effective way to ...
1
vote
1answer
333 views

Conditional one to many queries in mysql

I have a simple patients table and lots of Lab tests table. Every patient can have many Lab tests. What i want to do is to only query the tests which are already entered for that specific patient and ...
9
votes
3answers
17k views

Storing time with milliseconds in database

Just a quick question regarding storing "time" in a database. I'm logging the time of users runs which are in the format 00:00:00:00 (hours, minutes, seconds, milliseconds). I was originally going to ...
0
votes
2answers
120 views

ORACLE DB ERROR

We are currently experiencing a problem with Oracle DB 8. It is no longer starting and we get this message: ERROR at line 1: ORA-01113: file 19 needs media recovery ORA-01110: data file 19: 'E:\...
3
votes
2answers
523 views

What do I need to sync a local site office SQL Server with the Head Office SQL Server

The company has a desktop application powered by SQL Server from the head office that is dependent on an internet connection to our remote sites. Usually when we move to a new site there is a good ...
4
votes
3answers
3k views

Does ORDER BY on a clustered key effect performance?

Say I have a table clustered on PrimaryKey, and in all cases I want my results to be ordered by PrimaryKey so I additionally always ORDER BY PrimaryKey in all queries. Does this ORDER BY affect ...
4
votes
1answer
225 views

SQL Server - is it ok to store link table as a heap?

I'm trying to understand if it's a good practice to have non-clustered PK on link table: CREATE TABLE table1_table2(table1_id INT NOT NULL, table2_id INT NOT NULL, CONSTRAINT PK_T1_T2 PRIMARY KEY ...
3
votes
1answer
995 views

FREETEMPORARY on blob with no reference

In Oracle 11g, we are using XMLELEMENT to get records from tables. The problem seems to be, however, that we are calling SELECT XMLELEMENT(...).getClobVal() from DUAL; which is eating our temp ...
3
votes
1answer
4k views

Oracle not using index when > used in where clause

We have a relatively classic scenario where the date clause of the query generated by the application uses a "greater than" for a given date. Because there is no end clause to the date range, oracle ...
14
votes
2answers
5k views

Streaming replication and failover on PostgreSQL

I am doing a proof of concept on PostgreSQL replication. After the discussion on forum we decided to go with streaming replication as the performance is good compared to other solutions. PostgreSQL is ...
3
votes
2answers
4k views

Max number of tables (objects) in SQL Server editions (compact, express)

What are the maximum number of tables that you can have in: SQL CE4 SQL 2008 R2 Express Numbers here http://msdn.microsoft.com/en-us/library/ms143432.aspx I guess is for SQL Server 2008, but are ...
0
votes
3answers
999 views

SQL Server : primary keys advice to my whitepaper needed

I've tired to explain to every new junior developer in our r&d team why he should use Primary Keys and how to do that. So I decided to write small whitepaper, which every new developer should read....
2
votes
1answer
4k views

Write lock during mysqldump even using --lock-tables=false

When I try to dump an online database using --lock-tables=false, others cannot update the table. Are there any methods to solve this? As I am using MyISAM, does --single-transaction for InnoDB help? ...
1
vote
2answers
856 views

database normalization 2nf, 3nf

I am doing homework about database normalization. I have to decompose the table into 3nf form showing the steps here is the initial table: |-----------------------------------------------------------...
1
vote
5answers
4k views

SQL Server error log monitoring

In SQL server instance(s) I manage; I see a lot of activity and messages in SQL server error log for e.g. backup or transaction log backup completed etc.. We have quite a few databases in one instance ...
1
vote
1answer
3k views

SQL Server 2012 Create index with Sort In TempDb On - Gains False?

If I create an index e.g Create nonclustered index(Path, Value, Id) with(sort_in_tempdb=on); It doesn't fail but when looking at the index in SMMS, it says False. Any ideas why? EDIT: Can not find ...
2
votes
1answer
3k views

MySQL Workbench - Create new server instance error

When attempting to create a new server instance I get an error at the 'Test Settings' step of the creation wizard. The error: What check_admin_commands/local Operation failed: /usr/local/mysql/...
3
votes
1answer
1k views

Separate Schemas by Industry or by Application functionality?

I currently have a small retail/Point of Sale and an Education application running as on-premise custom solutions for different customers. I am planning to rewrite the app and host as a SaaS/web based....
4
votes
1answer
7k views

Rows with a variable number of columns?

I'm trying to design a database for a program that is storing and manipulating tweets off of Twitter. I'm using code to fragment a tweet into words, usernames, and hashtags, so I'm meeting @...
6
votes
1answer
500 views

in postgres, can one optimize a table across partitions?

in a database with many companies, segregating them using schema and search_path almost all access comes at the company level, that is, limited to a single schema. some data-warehouse and accounting ...
7
votes
3answers
10k views

Concurrent MySQL updates hang with InnoDB (on Amazon RDS)

I'm running into a problem where multiple MySQL updates being performed at the same time will lock up and takes several minutes to finish. I'm using InnoDB, so I'm confused as to why this could be ...
3
votes
2answers
8k views

“on duplicate key update” all the non-key fields mentioned in the insert

How can I update the field values mentioned in the insert portion without listing them again in the on duplicate key update portion? insert into tablename set keyname = 'keyvalue', fieldname = '...
4
votes
1answer
84 views

Why would you need to put a domain name when install a Oracle database?

When you install an Oracle database or instance, you are able to assign a domain name. An Example: SID: orcl Domain: world.com Service: orcl.world.com Why would it be necessary to add or ...

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