Structured Query Language (SQL). For questions about the language, not Microsoft SQL Server (tag sql-server).

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Strange SQL Server 2008 behavior while using XLOCK and ROWLOCK

I wrote this script without COMMIT in a new Query window (Query1): BEGIN TRAN SELECT [RegionID], [RegionDescription] FROM [Northwind].[dbo].[Region] WITH(XLOCK,ROWLOCK) WHERE RegionID = 3 and in ...
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2answers
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SELECT statement with an explicit list of columns and then an asterisk (*)

SQL Server allows to use SELECT statements similar to: SELECT FirstName, LastName, City, * FROM dbo.Customers When I try to execute such a query on Oracle database, I get the following error: ...
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2answers
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Using totals on aggregates to improve performance

I have two tables: details and totals of these details. Details (Slow solution): select OrderId = r.OrderId , TotalQty = SUM(r.Quantity) , ...
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How to update a table from a another table

I have one table A has column (id, field_1,field_2), and another table B has column (id,field_2) Now I want to merge table B to A, that means i want to update field_2 in table A to value of table B. ...
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What could be the reason for disallowing a sub query in the values clause?

For example SQL> create table dates(d date); Table created. SQL> insert into dates select sysdate from dual; 1 row created. SQL> select * from dates; D --------- 28-MAY-11 SQL> ...
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In Oracle how do I save a sequence.nextval in a variable to be reused in multiple inserts?

I'm writing a script to populate some tables with data for testing. I would like to write something like the following but I don't know how to do it (I'm Oracle 11g) SET ENABLED_USER_ID = ...
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How to insert values into a table from a select query in PostgreSQL?

I have a table items (item_id serial, name varchar(10), item_group int) and a table items_ver (id serial, item_id int, name varchar(10), item_group int). Now I want to insert a row into items_ver ...
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Patterns for setting up sharding for SQL Server 2008 R2, in order to handle large datasets?

I want to handle a large dataset (> 1 billion rows) in SQL Server 2008 R2. I heard that if you set up "sharding" or "horizontal partitioning", it makes it quicker to handle large datasets as it breaks ...
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1answer
336 views

Badly performing query plan after adding ORDER BY to Full Text CONTAINS search

The following query is proving beyond my abilities to fix - hope someone can help. SELECT top 100 Id, Name, InsertDate FROM Foo WHERE CONTAINS(FooText, '"test*" and "hello*" and "goodbye*"') ORDER BY ...
2
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1answer
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MySQL Update: why would rows matched change based on the set clause?

I ran an update query joining across a huge number of tables that updated one field, and it matched 29k some-odd rows. Running the same query with only an addition in the Set clause increased the ...
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2answers
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update stored proc ony fields that are passed to the proc and leaving others alone

i have a stored proc that does a simple update (see below). i want to update only fields passed and not the ones that are null. that is to say if i dont get a parm value for somethign i dont want ...
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Help with complicated MySQL query

I asked an earlier question about modeling MySQL data modeling help. The recommendation was the diagram labeled Multiple Tables for Role and Sponsor. Now I'm trying to write the queries and ...
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1answer
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Dealing with temp tables when I have not control over db variables

I have no control over things like tmp_table_size and max_heap_table_size, and so as our tables grow the time taken by queries requiring temp tables is growing geometrically. I am wondering if there ...
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1answer
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Are there situations where queries are formed geometrically?

The topic came up in this other question. We were discussing sign value on a primary key having any significance. If there are good times to use geometry in building queries the sign value could be ...
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1answer
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How can I alter the type of a money-column to decimal in PostgreSQL?

I have a table in PostgreSQL where one column "vat" has type money but I would like to alter it to decimal instead. How can I do it? I tried with: alter table my_table alter column vat type ...
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4answers
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How can I optimize this MySQL query further?

I have a query that is taking a particularly long time to run (15+ seconds) and it is only getting worse with time as my dataset grows. I have optimized this in the past, and have added indices, ...
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3answers
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Insert to particular location in Oracle DB table?

Suppose I have a table containing the following data: Name | Things ------------- Foo | 5 Bar | 3 Baz | 8 If I want to insert a row, so that the final state of the table is: Name | Things ...
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How can I use a default value in a Select query in PostgreSQL?

I would like to use a default value for a column that should be used if no rows is returned. Is that possible in PostgreSQL? How can I do it? Or is there any other way I can solve this? E.g. ...
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4answers
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Why does MySQL not have hash indices on MyISAM or InnoDB?

I have an application that will only select on equality, and I figure I should use a hash index over a btree index. Much to my dismay, hash indices are not supported on MyISAM or InnoDB. What's up ...
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2answers
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Relational Design - Multiple tables into one foreign key column?

Take a table that tracks meat purchases. It has a "meat_id" foreign key column to indicate what type of meat the purchase was. But, the different types of meat are unique in some way (such as USDA ...
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3answers
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Alternatives to concatenating strings or going procedural to prevent SQL query code repetition?

Disclaimer: Please bear with me as someone who only uses databases a tiny fraction of his work time. (Most of the time I do C++ programming in my job, but every odd month I need to search/fix/add ...
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LNNVL Justification

LNNVL is an oracle built in function that returns TRUE for conditions evaluating to FALSE or UNKNOWN, and returns FALSE for conditions evaluating to TRUE. My question is what would be the benefit of ...
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How do I show the binlog_format on a MySQL server?

How do I show the binlog_format on a MySQL server? And if I dont like it how do I set it to XX permanently? Where XX is STATEMENT, ROW or MIXED.
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3answers
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Can I automate the “on” statement from MySQL queries?

Background In the process of QA/QC, I am writing lots of queries with multiple joins. I am using MySQL. I would like to know how (if) I can simplify join statements, e.g. by setting default fields ...
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How to add sysadmin to user in SQL Server 2008 when no sysadmin accounts exist

I have a SQL server 2008 instance running. Unfortunately during testing I deselected the sysadmin rights for my login and now can't readd it (because I don't have sysadmin rights). There are no other ...
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Group By hour over large dataset

Using MS SQL 2008 I am selecting an averaged field from 2.5 million records. Each record represents one second. MyField is an hourly average of those 1 second records. Of course the server CPU hits ...
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2answers
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How to effectively query and aggregate a normalized SQL db?

In relation to Most efficient way to return multiple aggregates in a single stored proc? I have an email type application and want to select all the messages (inbox) for a user. The problem is that I ...
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4answers
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Do cross-joins get optimised by the client library?

Note This is deliberately database agnostic, I'm interested in how different implementations, er, differ. I came across Joins are for lazy people on SO, and it's made me question an assumption I'd ...
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2answers
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Stored procedure parameters using tsql functions?

Environment sql server 2005 sp3 I have a stored proc that takes an INT as input. I want to CAST a CHAR to an INT during the call to the stored proc. it seems I cannot do that. I get a syntax error ...
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4answers
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What is the difference between select count(*) and select count(any_non_null_column)?

I seem to remember that (on Oracle) there is a difference between uttering select count(*) from any_table and select count(any_non_null_column) from any_table. What are the differences between these ...
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votes
2answers
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Sp_helptext Error

I am using sp_helptext to list some stored procs instead of going through the ui. I am having a problem with the naming convention we have chosen to adopt. I have a stored proc nameed [Test.FooBar]. ...
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Creating centralized DBA database

We have 200+ servers and I am thinking about creating a centralized DBA database where it logs backup, errors, space jobs and generate reports on SSRS. I am not sure where to start and I would highly ...
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DBCC CheckDB Consistency error on an empty table [duplicate]

I restored a DB from SQL Server 2000. I ran DBCC CHECKDB on SQL Server 2000, and it did not report any errors. What could be the reason behind a DBCC CHECKDB reporting a consistency error on a empty ...
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2answers
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Query PostgreSQL 9.0 table on foreign key value?

Noob-type question: Say I have two tables, candies and colors. The colors table holds just code/value pairs like 01 yellow, 02 blue, 03 green, etc. and is referenced in the candies table by code. ...
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2answers
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Sql Server output parameters

Is there a way to use named parameters when getting the output parameters of a stored proc? Currently my knowledge of output parameters is very limited. It looks like I have to use them in order of ...
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SQL Server - RangeX-X and RangeI-N locks

I came to a dead point in a deadlock analyze. According to msdn: RangeX-X are Exclusive range, exclusive resource lock; used when updating a key in a range. RangeI-N are Insert range, null resource ...
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1answer
186 views

MySQL queries in SQL-Server?

How can we best use our existing MySQL queries with SQLserver? Alternately, what type of changes do we need when we are converting our database server from MySQL to SQLServer?
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does DBCC ShrinkDatabase do a Reorganize of files?

does DBCC ShrinkDatabase doa Reorganize of files? Basically does it mimic the same process as if i checked Reorganize in the GUI?
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2answers
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Calling a stored procedure in a stored procedure

Environment sql server 2005 My question is Calling a stored proc within a stored proc within another stored proc. When is this type of development detrimental? In order to promote code reusablity ...
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2answers
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MAX for each subset

I have a table that looks like this: +---------------------------------------------+ | EVENT_ID | ITEM_ID | PERSON_ID | EVENT_DATE | +---------------------------------------------+ | 123 | 1 ...
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1answer
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Sql DateDiff Question

Select distinct DATEDIFF(ww, GETDATE(), siparis_test) AS Hafta The first day of week is sunday in the above function. How can I change it so that monday is the first day? Thanks in advance.
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1answer
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What is a residual predicate?

Although I was able to find the definition of predicates online at MSDN: Is an expression that evaluates to TRUE, FALSE, or UNKNOWN. Predicates are used in the search condition of WHERE ...
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3answers
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Query to normalize table/combine row text

I have a table (call it oldTable) with columns like so: ID (int),Rank (int),TextLineNumber (int),SomeText (varchar) The primarykey is multi-part: ID+Rank+TextLineNumber. I'm trying to ...
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6answers
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Running a database without constraints

We're looking at utilizing a new proprietary high performance database engine for OLAP and OLTP scenarios. One important aspect of it right now is that it does not support foreign key or other ...
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2answers
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datatypes in sql server , difference between similar dataypes, numeric, money , decimal ,float

What datatypes could be given to this value --> 45.58 Could these be given: numeric money decimal float What's the difference then? Which one would be the best to use?
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2answers
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How to get a user's friends' names?

I have a users table and friends table. The user with ID 1 has 4 friends (with IDs 2,3,4,13). I want to get names and surnames of users 2,3,4 and 13. I can to it with standard queries but it will slow ...
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How to choose the last recorded added without sorting

I've got this simple table: RecordID (int PK), UserID (int FK), DTime (datetime), Length (int) I need to run a simple query: SELECT TOP(1) * FROM uTable WHERE UserID = @userid ORDER BY DTime DESC ...
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1answer
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Select statement to retrive xml output as below

Hi could someone provide me some clues or solution to retrive record sets like below note: i read the msdn documentation but leads me no where but hair loss :( Just for the assumption think i have 2 ...
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How do I Create Tablespace in Oracle 11g?

I am not too savvy in Oracle, and I have been trying to create a TABLESPACE, which keep on giving me an error message of invalid file name. Below is the syntax that I have used: SQL> create ...
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Print Parameters in Dynamic SQL

I've used dynamic SQL for many tasks and continuously run into the same problem: Printing values of variables used inside the Dynamic T-SQL statement. EG: Declare @SQL nvarchar(max), @Params ...