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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2
votes
1answer
367 views

UDF performance suddenly degraded

SQL Server 2008 R2 I know this is a common problem (eg: http://connect.microsoft.com/SQLServer/feedback/details/524983/user-defined-function-performance-is-unacceptable) - but ive only just learned ...
7
votes
2answers
2k views

PAGE compression in SQL Server effect on running queries

I am planning to apply PAGE compression to some of the big tables in my database (DW to be precise). These tables are fairly big with over 15 Billion rows. When I applied the compression in test ...
0
votes
2answers
2k views

Difference between chained and migrated rows

What is the difference between chained and migrated rows? Also what query should be used to display these rows? (I'm using Oracle 11gR2 database)
-1
votes
1answer
73 views

Can I make that connection?

If I have a column with data type varchar(max) in a table that contains a big piece of text, can I make a connection between a word or a sentence in that text with another word or a sentence in ...
2
votes
2answers
976 views

Why does my query run faster after I force full table scan?

I have a MERGE statement that took forever to execute the select as the table it is running from (SUB_DATA) is rather big (read 1.4 Tb, 700 million rows). My SELECT looks like this. SELECT ...
0
votes
1answer
265 views

Patients profiles database

I am making software for patients in hospitals. I want to make an option that if a doctor has prescribed a drug that interacts with another drug that the patient already uses, a warning will appear ...
3
votes
1answer
253 views

SQL query returns different results when index is dropped

In SQL Server 2000 SP4, I have a query SELECT <fields no aggregates> FROM PS_VED_VCH_TAO5 A ,PS_BUS_UNIT_TBL_AP B ,PS_RT_DFLT_VW C WHERE A.PROCESS_INSTANCE = 594170 ...
-1
votes
3answers
4k views

Conversion failure varchar to int

When running this code: declare @SQL NVARCHAR(max); declare @intFlag INT; set @intFlag = 2; SET @SQL = ' SELECT * into [##tmp1] FROM servicesstats_0511_0412 s WHERE department=''ACC'' and ((SELECT ...
1
vote
1answer
282 views

postgresql pgadmin3 queryconnect attribute does not work

I'm using Fedora 17 and pgadmin3 to auto-connect to a postgresql database with one button click. Every time I want to run an SQL statement, I have to do 4 steps, (open pgadmin3), (connect to the ...
2
votes
1answer
6k views

query to find closest lesser date

I have a table with rates. each rate has an effective starting date. (the ending date of any rate is implied by the existence of a record with a newer effective starting date.) I also have a table ...
1
vote
3answers
309 views

Same query taking 0.2 sec in Oracle database but 4 mins in SQL Server

SELECT A.Field1 FROM Table1 A INNER JOIN Table1 B ON A.Field2 = B.Field2 AND A.Field3 = B.Field3 AND A.Field4 = B.Field4 AND B.Field1 = "string1" AND B.Field2 = "string2" AND A.Field5 = (SELECT ...
4
votes
2answers
595 views

How should I best design the tables and relationships, given the following rules?

In a Pawnshop business, customers pawn, sell or buy items. A contract which specifies the customers information, the items, and the terms and conditions is created whenever customers pawn, sell or buy ...
3
votes
2answers
216 views

Finding violations of the symmetry constraint

Suppose I have a table Friends with columns Friend1ID, Friend2ID. I chose to represent each friendship with two records, say (John, Jeff) and (Jeff, John). Thus, each pair of friends should show up ...
5
votes
3answers
1k views

Many-to-Too-Many Relationship

I'm working on a book database. And among others, I have the following two tables (a bit simplified for the question): tblBook: ID, Title tblPerson: ID, Name Note that the tblPerson table contains ...
0
votes
3answers
60 views

Query Optimizing Request

I am very sorry if this question is structured in not a very helpful manner or the question itself is not a very good one! I need to update a MSSQL table call component every 10 minutes based on ...
1
vote
1answer
164 views

Stored procedures and network congestion

When I went to an interview, the interviewer asked me "what are the benefits of stored procedures?" and I started answering but when I said "It reduces network congestion", he suddenly said "no, it ...
1
vote
2answers
100 views

Easy SQL, embedded select

I have a table of zip codes with latitudes / longitudes. Unfortunately it doesn't seem to have a few zip codes. I would like to try to approximate the latitude / longitude based on other zip codes ...
2
votes
1answer
4k views

Oracle error “too many values”, must be solved with nested SELECTs

I have hit upon a "too many values" error in Oracle, when working with some intricate nested SELECTs. A simplified description of my problem, on a toy problem describing the hierarchy in a company. ...
4
votes
1answer
1k views

Does UPDATE INDEXES work for local indexes?

I have two tables in Oracle 11.2. First is partitioned and has local index (non-prefixed): CREATE TABLE table1 (col1 INT, col2 INT) PARTITION BY LIST(col1) ( PARTITION p1 VALUES(1), PARTITION ...
2
votes
3answers
238 views

MySQL data view

I have a table that looks like this: +----------------------------------------+ |Name | kode | jum | +----------------------------------------+ | aman |kode1 ...
0
votes
1answer
100 views

Logging of incorrect row in SQL Server Integration Services

I newbie to SQL Server Integration Services and I have a problem: Data loaded from file looks like this: 1 'a' 'b' 2 'a' 'b' 1 'c' 'd' And this rows would be loaded in table like this: CREATE ...
2
votes
1answer
459 views

Recovering from a stuck query

I have a big DELETE query (deleting 20M rows from a 600M row table with condition according to indexed column) that is stuck - running already for 17hrs. Because it's an InnoDB table, killing it will ...
3
votes
1answer
122 views

query discrepancies on very large postgres table

I have a fairly large table (25m entries) which stores tracking data, I am not a postgres admin by trade so this may be a simple problem. these two queries although similar are taking massively ...
1
vote
1answer
99 views

sqlite database: advanced SQL or redesign

I've been programming for several years, but I'm pretty new to SQL(ite). I'm designing a database for a sort of a bookkeeping program. What I've got so far: orders (o INTEGER PRIMARY KEY, ...
0
votes
1answer
1k views

Access query to select multiple records with matching field

I have a table with a list of people ([FirstName], [Surname], [Age]). Some of these people are in the same family. I'd like to return a list of people who have another family member in the table (same ...
5
votes
2answers
3k views

Is SELECT ROW_NUMBER() guaranteed to return results sorted by the generated row numbers?

E.g. consider the SQL query: SELECT A.[Name], ROW_NUMBER() OVER(ORDER BY A.[Name] ASC) FROM [FooTable] AS A Here I observe the results being returned sorted by A.[Name]. If I change the ...
2
votes
1answer
668 views

Populating an empty table using loops, conditionals, and accessing multiple tables

This question pertains to a MySQL database, although, in the end, this may be database neutral. I am trying to populate an empty table (let's call it NewTable) that I created. The data population is ...
7
votes
1answer
657 views

Is the optimisation fence behaviour of a CTE (WITH query) specified in the SQL:2008 standard? If so, where?

I see frequent references to WITH queries (common table expressions, or CTEs) acting as an optimisation fence, where the server isn't permitted to push filters down into the CTE queries, pull common ...
2
votes
3answers
1k views

Is there a way to tell SQLCMD not to output rows to text or a file?

I am testing the behavior of a SELECT statement that returns 170,000,000 rows using SQLCMD. My goal is to cut out the time spent receiving the result-set on the client end (the time the process shows ...
4
votes
5answers
279 views

How much does an index need to narrow the results of a search in order to be useful?

How much does an index need to narrow the results of a search in order to be useful in speeding up queries? Some examples all across the spectrum: A column for storing true/false values obviously ...
1
vote
2answers
118 views

How can I append a column to an inner SQL statement?

I have two tables that have the same structure except one has an additional column that should be auto-incremented. Sequence and trigger are defined. I want to copy all data from one table to ...
0
votes
1answer
329 views

how to pass url value to index [closed]

How to read the value from URL and compare with index that i have created in MYSQL table. I have a form where provide list of selection using drop down list and i pass the selected value to the next ...
1
vote
2answers
241 views

SQL query based on foreign key relationship

I have two tables, a Project and an Action: Project has the following fields: project_name Action has the following fields: action_name project status There is a one-to-many relationship ...
2
votes
0answers
427 views

MySQL database structure: more columns or more rows [closed]

I collect how people tag topics with categories in table like: ID | topic_id | votes_Category_1 | votes_Category_2 |.......... | votes_Category_12 This table holds 1 row per topic and dynamically ...
3
votes
2answers
1k views

Blocking drop database command

I created a MySQL database and created a new user dedicated to that database with all permissions. The new user then proceeded of dropping the database in addition to all tables. I need to block that ...
10
votes
1answer
3k views

How to preserve the original order of elements in an unnested array?

Given the string: 'I think that PostgreSQL is nifty' I would like to operate on the individual words found within that string. Essentially, I have a separate from which I can get word details ...
1
vote
3answers
3k views

Putting SQL Server data files in a different partition

I have a SQL Server and I put the data files (the .mdf) on a different partition. Windows runs from C: and the data files and logs are on D: Is it advantageous or disadvantageous to separate the ...
13
votes
5answers
12k views

Alter table on live production databases

How do most "popular" (MySQL, Postgres...) database system handle altering tables on live production databases (like adding, deleting or changing the type of colums)? I know the correct way is to ...
2
votes
0answers
117 views

QBE Query By Example. How does it handle OR conditions?

I've been looking at implementing QBE into an application but need more information on how more complex queries work. How does QBE handle "OR" conditions? For example when searching a telephone book ...
1
vote
2answers
296 views

correct security and user setup for SQL Server database

I am currently on setting a sql server database on a database server. A front end web application running off a web server communicates to the database. What is the best approach for setting up users ...
0
votes
1answer
88 views

SQL Query for the following structure

Given the following type of data structure. ID NAME TREELEFT TREERIGHT PARENT 1 XYZ 1 2 0 2 ABC 3 6 0 3 DEF 4 5 ...
9
votes
3answers
499 views

Are these two queries logically equivalent?

Are these two queries logically equivalent? DECLARE @DateTime DATETIME = GETDATE() Query 1 SELECT * FROM MyTable WHERE Datediff(DAY, LogInsertTime, @DateTime) > 7 Query 2 SELECT * FROM ...
5
votes
1answer
178 views

GROUP BY on a dependent field

Let's say I have a SELECT statement as follows: SELECT ..., field1 FROM ... GROUP BY field1 Now let's say I want to return a second field, field2. As it happens, field2 is functionally dependent ...
1
vote
1answer
273 views

GROUP_CONCAT with ORDER BY , but results are not ordered

The following query works fine SELECT *, (SELECT GROUP_CONCAT(url SEPARATOR '$$' ) FROM project_photos WHERE project_id = projects.id ORDER BY priority) AS images FROM projects WHERE catID = 2 LIMIT ...
5
votes
1answer
377 views

Does SQL manage foreign key constraints in terms of Insertion?

Say I have a table tbl1 with data A1 and A2, where A1 is the primary key. Then I have another table tbl2 with data A3 and A1, both together being the primary key, referencing A1 as a foreign key from ...
1
vote
1answer
110 views

Getting the page name from a web URL in Oracle

I have a list of page URL's in my database table under the column heading URL. There are many different prefixes on each page name for example: Test1/Admin/Page7.asp Test1/One/Page3.asp ...
1
vote
1answer
40 views

Order questions depending on answer votes

I'm really curious about how to create an SQL query to order questions depending the votes_up and votes_down. (The votes can be the sum of both, votes_up + votes_down.) Question has_many answers ...
0
votes
3answers
2k views

ORA-01562: failed to extend rollback segment number 11

I´m trying to execute this query into a SP DELETE FROM table SC WHERE SC.evaluationMonth= 'Some month'; COMMIT; But for this month there are something like 10 million records. So I get the ...
0
votes
2answers
206 views

Print variable of same datatype

I am looking for to print two variables of same datatype I have something like this declare @one int ,@two int set @one=1 set @two=2 print @one+@two obviously it will give a result 3 but I need ...
1
vote
1answer
323 views

Index strategy for a Queue Table, getting rid of filesort

I am trying to get rid of a filesort operation (and preferably also optimize a bottleneck query). We are using an innodb mysql table as a queue to process various incoming business activities. It is ...