DO NOT USE this for questions targeting Microsoft SQL Server, use the tag sql-server instead. "SQL" is an acronym for "Structured Query Language", it is used in relational database management systems (RDBMS) to query, update, delete, and insert data as well as modify the structure of the database. ...

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4
votes
1answer
722 views

Store SSRS Report export directly to database

As a requirement, I have to check for a certain condition on some data in the database, if the condition is true, then I have to create a pdf report and store it on a table. I have everything set up ...
1
vote
1answer
488 views

mysql query - how to delete duplicates based on highest int?

I'm running a reverse auction website and I need to delete the duplicate bids and keep only the highest amount . lastPriceBid_rounded is the "amount". The duplicate is defined by the userId. ...
3
votes
1answer
4k views

The server principal “<mydbuser>” is not able to access the database “<mydatabase>” under the current security context

When I try to install a new database, I'm getting this error from SQL Server 2008. The server principal "<mydbuser>" is not able to access the database "<mydatabase>" under the current ...
2
votes
1answer
3k views

Select the top 5 records and the specific column from each table in the same database

I have 50+ tables in a database. I don't want to use the following SQL on each table in a database. select top 10 * from {table_name} So, is it possible to display the first 10 records PLUS only ...
0
votes
3answers
4k views

How to select the first 10 records for each table in the same database using sql

I have 50+ tables in a database. I don't want to use the following SQL on each table in a database. select * from {table_name} So, is it possible to display the first 10 records for each table ...
7
votes
2answers
466 views

What is the purpose of the USING parameter in SQL?

Working with some code on a standard MySQL database, and I came across this statement: SELECT * FROM foo LEFT JOIN bar USING ('bar_id') WHERE foo_id = 1 What's throwing me is: what is USING for, ...
4
votes
1answer
81 views

Index Evaluation

I have been doing some index evalaution on a table and this is the first time I have ever looked at how well indexes are performing so and would like some advice on a certain index. The non ...
2
votes
0answers
209 views

Limit Output Flat File Size In SSIS

I am using Flat File Destination to export my data's to a Text file. I need to limit the output File size to 1 MB. Is it possible?
0
votes
2answers
68 views

some tips on setting up sql server database server

I am currently setting up a new sql server database server with databases. It is supplied by a third party company. I need to request access for them around ports etc. I would like to be able ...
2
votes
2answers
1k views

What is the difference between using varchar(100) and varchar(255)?

I want to know difference between varchar(100) and varchar(255) in terms of memory usage and programming problems of using more memory.
3
votes
1answer
67 views

Special ordering

I have a hierarchical query but I don't manage to order it as I want. I have a column named sequence that indicates how to order it but the data is kinda mixed up and I cant do it properly. This a ...
1
vote
2answers
191 views

Suggestion for storing a lot of simple data

I'm looking to crawl a lot of webpages (500,000,000,000) records and be able to store the linking structure for a later date. The way I planned on laying out the database was as follows: 2 Tables ...
7
votes
2answers
829 views

Is there any difference between putting a column alias at the start or the end of the column definition?

I've always seen and written my column aliases as SELECT 1 as ColumnName but today came across a query that used SELECT ColumnName = 1 Is there any difference in how these two queries get ...
3
votes
1answer
74 views

Locating row in index page

In clustered index, we have root, intermediate and leaf level pages. Every page has few records where indicating range of pages from level below. How SQL check whether some index key belong to ...
0
votes
1answer
72 views

Faster joining on 'most recent' related rows

I have a bug tracking application. The bug table stores very little, because every state change to a bug happens by adding a comment. For example, the current state of a bug is determined by the state ...
0
votes
2answers
88 views

How to organize a single query to several sql servers?

I need to make an inner join sql query to several SQL Servers (one is 2000 and another is 2008 R2). The query is like the following: SELECT k.ID, k.NAME, k.BIRTH, l.PROFILEID FROM ...
0
votes
0answers
345 views

Understanding the time difference between data grid initial display and export/full display using Toad for Oracle

I am trying to run a query on a local Oracle DB and output the results to a .CSV file. The query runs in a decent amount of time (usually less than 5 minutes), but returns tens of thousands (possibly ...
1
vote
1answer
655 views

How and what is the most efficient way to join two tables, retaining a particular field from both?

I have two tables, with the following columns: Table 1 ID Component Data1 Data2 Table 2 ID Component Data3 Data4 If I have rows in these tables, with items Component1, Component2, Component3, ...
4
votes
1answer
495 views

Query records that chain together based on date gaps

I have a table in SQL Server 2012 with the below simplified schema and I need to define a query that grabs the most recent record and then returns the chain of records that have less than 30 days of a ...
1
vote
1answer
144 views

Mysql setting a record as deleted or archive

Is there any way to omit some records in mysql select statement and not deleting them? We can easily add a column for example deleted and set it to 1 for deleted ones and keep them but the problem is ...
4
votes
1answer
111 views

How to get the information of the optimizer of sql server?

The info like total optimization time, the time spent on each stage of optimization, the number of alternative plans and the cost of each alternative plan. Is there any way to get these info using sql ...
1
vote
1answer
470 views

Can I install sql server on Win XP machine with user profile on D drive?

Is it possible to install sql server on a windows xp machine where the user profiles are created on a non system root directory, that is, on D drive rather than C drive? I am trying to install SQL ...
2
votes
1answer
375 views

Table Statistics Affect Index Only Query?

We have a query that was getting poor performance. The root of the problem could be reproduced using a simple query accessing only one index to retrieve one column (the indexed column) from eight ...
1
vote
2answers
3k views

SQL Server - backup / restore schema only (not a duplicate if that's what you're thinking!)

We have a DB on over 100 servers of which we want to backup / restore the structure of just 1 at a time to a specific UAT database. They're all called the same thing but vary in terms of schema - ...
4
votes
2answers
568 views

How to sort category by path and sort order?

first of all I am sory for my english. My category structure is shown below. My purpose is to get category structure with single query. I sort my table by path and I get category tree. sort_order : ...
1
vote
1answer
919 views

Strange behaviour of a query with order by and rownum on Oracle's Exadata server

I am executing the following query on two different database servers: SELECT start_date, end_date, resort_id FROM employee_activity WHERE employee_id = 27 AND start_date < ...
0
votes
2answers
2k views

Does MYSQL join before LIMIT?

Imagine that I want to populate the last 10 questions of stackoverflow. I have a table that keep the questions list, a table to keep the question info, a table to list question's asker. Now imagine ...
7
votes
2answers
4k views

How to retrieve foreign key constraints data

I'm looking for a query allowing to retrieve foreign key infos (each line: referrencing table & field, referrenced table & field) of an entire schema. I've found this, but does not gives all ...
1
vote
1answer
585 views

SQL - double column used from primary key with autoincrement

I am user the following as primary key in the SqlDB: I am doing the Index as Autoincrement, but it is autoincremented in general not per user. Example userid=1,index=1, then insert another for ...
3
votes
1answer
135 views

How to search for an ID and its descendants in this query?

I have the following tables: Project Unit ------------- --------------- ID | IDUnit ID | IdParent I have to select all projects that have the IDUnit ...
1
vote
3answers
2k views

SQL services wont start due to incorrect drive letter after windows restore

SQL services wont start due to incorrect drive letter after windows restore Had a server crash, was successfully able to reinstall windows and restore the server SQL and all the necessary services ...
0
votes
1answer
45 views

Need Some SQL help [closed]

I need to pass the following SQL statement: UPDATE table_products SET shipping = "a:5:{s:16:"min_items_in_box"; i:0;s:16:"max_items_in_box"; ...
2
votes
1answer
81 views

Response On Database Failover

Let say, that I have principal server named P, and mirror server named M. I've got 7 databases that are in server P, and 7 mirror databases on server M. Whole engine works fine when we are talking ...
2
votes
2answers
1k views

how does SQL Server 2008 handle joins internally?

for example, I have tables: User and Order User Table: UserId, Name, Address, Phone, Age Order Table: OrderId, UserId, Date, Item, Quantity SQL: select User.Name, Order.Date From Order JOIN User ...
2
votes
1answer
152 views

Is there a name for a query that returns results which have sub headings?

I inhered a set of queries / macros from the previous employee in my position and one of the other people here showed me a query result (output from when the query worked correctly) which had ...
0
votes
1answer
587 views

Optimising MySQL query with lots of self-joins

I have an entity_relationship table that describes relationships between entities. Each relationship will have 2+ entities involved. In some cases it can be said that one entity is a constituent of a ...
1
vote
1answer
58 views

Correct data model for users with clients

I have an application where users are granted access. Part of the system allows users to have their own 'clients'. I have a users table ******************************** users ...
1
vote
1answer
166 views

Multiple primary keys

I am new to database design and have been looking at some example data models here. One thing I don't understand is if you have a table like client_addresses from the link above: ...
8
votes
3answers
1k views

SQL Database Structure for RESTful API

I am creating a RESTful API. I am struggling to decide on the best way to design my database tables around my resources. Initially, I though a table per resource would be a good way to go, but I'm ...
0
votes
1answer
275 views

Create a VIEW that spans 3 tables

Sorry if the title is not clear - feel free to improve. Here are 3 tables (not all data is relevant to the question): CREATE TABLE `content` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, ...
2
votes
2answers
6k views

ORDER BY clause is allowed over column that is not in SELECT list?

In theory, every statement in SQL Server create virtual table passed to next statement. In other words, when FROM and Where clause are finished, next step is SELECt columns from virtual group created ...
5
votes
1answer
273 views

Logical reads amount difference with almost identical indexes

I'm trying to figure out why two identical queries are taking slightly different times when executed under two indexes that are almost identical, in SQL Server. The mentioned query is quite simple, ...
2
votes
1answer
124 views

index doesn't work properly

I have this query SELECT user_id, MAX( highscore ) AS highscore, stage, COUNT( * ) AS count FROM single GROUP BY user_id, stage table engine is innodb, plus I haven't use any indexes except one key ...
1
vote
1answer
43 views

simple query is not using indexes

My query is not using indexes. it was taking around 5 seconds. output is 500 rows only. it is a simple query Please find the explain plan and table structure here. Explain Plan mysql> explain ...
3
votes
2answers
4k views

Can someone explain why select with nolock will query a potion of updated data?

I was reading the answer from here (from stackoverflow, I think should ask in here) NOLOCK means placing no locks at all. Your query may returns portions of data as of before UPDATE and ...
4
votes
1answer
130 views

repeatable read and nolock

Does anyone know what the net effect of having a block of t-sql with a transaction isolation level of repeatble read and then inside having a select with nolock. Does the nolock become invalid ...
4
votes
2answers
700 views

Restore SQL Server database from .sql files

So we had an encrypted database that puked and killed our whole SQL Server setup. Sucks about our data, but we were smart enough to have our data structures / stored procedures / functions in Git The ...
8
votes
2answers
5k views

Create View in specified database with dynamic sql?

I am writting a dynamic sql to drop and create view in different database. So I wrote: set @CreateViewStatement = ' USE ['+ @DB +']; CREATE VIEW ...
0
votes
1answer
171 views

MySQL: select a row if that row is equal for every user

In my database I have 5 fix users, lets say user1, ..., user5. Furthermore I have a table month(name, finished, month, year) where name is VARCHAR (the name of one of the five users) and the ...
0
votes
1answer
249 views

Postgresql: Return Unique Rows

I'm using postgresql and I have a large database. A simplified version of the datastructure for my table looks like this: id (primary unique key), data, userID 1, foo, 4 2, foobar, 4 3, lala, 5 4, ...