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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18
votes
1answer
30k views

How to force drop database in SQL Server 2008

I'm trying to force drop a database, but after dropping the database, when I try to recreate the database, I'm getting the error cannot create file C:\Program Files.....[databasename].mdf because ...
6
votes
1answer
2k views

Postgres Update, limit 1

I have a postgres database which contains details on clusters of servers, such as server status (active, standby, etc). Active servers at any time may need to fail over to a standby, and I don't care ...
0
votes
0answers
6 views

Why is there a difference in CSV Export Results of Oracle SQL Developer and SQL Plus Spool

When I export data from SQL Developer GUI, setting format: csv, left enclosure: ", right enclosure: ", and Encoding: UTF8, I get data exactly the way that I need it for processing in Python. ...
0
votes
2answers
154 views

How to import into database when records contain multi-line data

I am setting up a new database and I want to import lots of data from multiple spreadsheet files. One of the fields in these documents contains an array of data, each item declared on seperate rows as ...
0
votes
1answer
24 views

Script works but Im not sure this is the best format

I have a survey table which contains mostly integer. I want to make it readable for end user so I use select statement as below: SELECT CASE s.Country WHEN 1 THEN 'One' WHEN 2 THEN 'Two' ...
-1
votes
0answers
7 views

Filter several columns and order it from a table

I am looking to filter it for values 1 and 2 (door open/shut)… and ensure it is sorted in DATE and TIME order…. and finally by bus stop id. From that picture ... Anybody can help me with it? Thank ...
0
votes
1answer
40 views

Using Like with variables?

I have an odd situation where I have a column called (TransmittalNumber) with datatype of VarChar (75) in a table named (Transmittal Sheet). I want to query this table to find the transmittal numbers ...
1
vote
3answers
3k views

Missing DB on linked server

So there is a linked server. However, I am not currently able to view all databases associated with that linked server from within SSMS after expanding the catalog dropdown. It is my understanding ...
0
votes
3answers
440 views

Mysql - How to Optimize Retrieval Time in a Table

I have query like this! which has 200 million Records in a single table.. I am using BTree Indexes in my table... mysql> select COUNT(DISTINCT id) from [tablename] where [columname] >=3; ...
0
votes
0answers
9 views

When to use tags vs binary fields in a constituent management system?

I have a table of Constituents and I want to track yes or no qualities like: are they a teacher? are they an elected official? are they philanthropists? There will be less than a dozen of these ...
1
vote
2answers
19 views

Troubleshooting high disk read - buffer cache query

I have a table tbl_Table1 that is about 5 GB in size and has millions of rows. It has these columns: ID, ContractID, Person, Address1, Address2, and many more. One clustered index on the PK, ID. I ...
0
votes
1answer
20 views

Is it possible to select distinct values in a json document using PostgreSQL?

I have a column that is using the JSON type. I would like to perform a query to select all distinct records for a particular field in the JSON string: I.e. given these three documents { id: 1, s: ...
0
votes
1answer
230 views

Data Analysis with MongoDB or MySQL

I have a need for processing some data in order to come up with some statistic. This is the scenario: Each user can answer several questions from the question list. They pick their answers from a ...
1
vote
1answer
43 views

Find all tables that are related to a view recursively sql server

I have a view-A that is comprised of other views (View-B View-C) and I would like to list all the tables that used by View-A (which would include the tables used in View-B and View-C). When I use ...
0
votes
1answer
27 views

mysql Quiz leaderboard filter by points, time taken

I have a quiz report table which shows a report for every quiz a user takes. I need to create a leaderboard from this, which shows the top users best score, filtering by points and then time taken. ...
0
votes
1answer
122 views

Connect by prior - multiple fields and query efficiency

I have 2 tables one of which defines the hierarchy for the other equipment id desc 1 item1 2 item2 3 item3 4 item4 5 item5 6 item6 7 item7 8 item8 ...
3
votes
5answers
2k views

Two-sided UNIQUE INDEX for two columns

Creating a table with composite PRIMARY KEY or using UNIQUE INDEX for two columns guarantee uniqueness of col1, col2. Is there a tricky approach to make the reverse order of two columns UNIQUE too ...
3
votes
2answers
475 views

Is there a way to calculate yesterday / today of last month / year in SQL?

Is there a way to calculate today (and yesterday) of last month (and last year) in SQL? Assuming today is 26-May-2015 then how to find? Today of last year i.e. 26-May-2014? Today of last month i.e. ...
-3
votes
0answers
13 views

How to convert the rows to column in View from old design to New design [on hold]

How to convert the table structure in view from old design to New design .
0
votes
1answer
115 views

how to select top ID from join operation and staging tables

I have this inner join from staging and operations table jobsCode I want to select the top surrogate key ID and get the Start_Date from this join my problem is my Query rerunning 2 records original ...
4
votes
1answer
52 views

Warning for missing statistics in execution plan

I have a situation that I cant understand. My SQL SERVER execution plan tells me that I have missing statistics on the table, but the statistics is already created. Please see the screens. But if ...
16
votes
5answers
71k views

How to select the first row of each group?

I have a table like this: ID | Val | Kind ---------------------- 1 | 1337 | 2 2 | 1337 | 1 3 | 3 | 4 4 | 3 | 4 I want to make a SELECT that will return just the ...
2
votes
1answer
2k views

Error Code: 1133. Can't find any matching row in the user table

Im reading O'Relly "Learning MySQL" and it says that you can create a user in MySQL by doing just this: mysql> GRANT ALL ON *.* TO 'jill'@'%.invyhome.com' IDENTIFIED BY 'the_password'; Query OK, 0 ...
1
vote
1answer
84 views

Slow Performance caused by Correlated Sub-queries & Clustered Index Seek

I'm running a query in which one of the tables (FIELDDATA) has nearly 400,000 records which is taking more than 2 minutes to execute. I ran the execution plan, and noticed that the clustered seek ...
-3
votes
0answers
31 views

What are some good puzzles to test my Advanced T-SQL skills? [on hold]

What are some good puzzles to test my Advanced T-SQL skills ?
0
votes
1answer
133 views

How to check mysql password change and other events logs

Recently someone change my phpmyadmin password and drop database I think it was sql injecting. Now I want to find information about this like when, how and who change my password Please tell me ...
8
votes
1answer
396 views

Why is SELECT * much faster than selecting all columns (in a different column order) 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 ...
2
votes
1answer
356 views

Cross Apply without a function

I would like to run a query very similar to this on one of my production databases: -- Setup the table (Already there in my real scenario) create table dbo.MyTable(MyValue int, MyGroup varchar(5)) ...
0
votes
1answer
23 views

How to insert UNIQUE IDs values from several tables into events table

I have a table called events defined as follow: rep_id, hcp_id, brand_id, email_id and content_id is the IDs in other tables. event_type should be kind of array containing this values: [ ...
3
votes
1answer
58 views

How is encoding done in SQL database tables for pattern matching?

Are strings in table columns represented as bit patterns or Unicode? Does the database engine bring them into memory in a different representation character set from the disk-persisted ...
1
vote
2answers
30 views

Repeating rows of date intervals based on another table in Oracle

I have a table of maintenance plans with date intervals between each required maintenance period. Fiddle: http://sqlfiddle.com/#!4/af742 create table maint_sched (maint_id number, start_date date, ...
0
votes
1answer
148 views

MySQL-How to find that value in a column is subset with all other values in same column multiple time

I have a table named as Team where table contain 3 column (ID,Team,Task). Its datatypes are (INT,VARCHAR(255),INT). Below you will find a sample table where I would like to perform the query on column ...
3
votes
1answer
68 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 ...
0
votes
2answers
179 views

What's faster: two UPDATEs with WHERE (in / not in) or one UPDATE with CASE?

What's best performance wise, two separate UPDATEs: UPDATE table1 SET enabled = 0 WHERE code NOT IN ( SELECT id FROM table2 ); UPDATE table1 SET enabled = 1 WHERE ...
2
votes
1answer
1k views

Split comma separated entries to rows

I have a Table like this: | ID | OtherID | Data +--------+-----------+--------------------------- | 5059 | 73831 | 5103,5107 | 5059 | 73941 | 5103,5104,5107 | 5059 | 73974 | ...
2
votes
1answer
2k views

Extract MySQL information from a compressed tar.gz file

I have a back up-of a MySQL database which is contained in a .tar.gz file - I need to restore it. I've never had to do this before. The only way I can access the database is through phpmyadmin. There ...
1
vote
2answers
114 views

Check entry based on entry in another column

Still fairly new to databases and SQL, so bear with me. I'm trying to check whether or not data can be inserted depending on data in another column, create table Table1 (PaymentType varchar(5) ...
0
votes
0answers
19 views

For any SQL query, do there exists a unique translation into relation algebra

I have been studying databases and I understand that for each query that a database user type, the DBMS translate them into relational algebra operations before applying them to the database. My worry ...
0
votes
1answer
49 views

Arithmetic operations on a table

can anyone give me some advice on the following situation: I have two basic tables: Then a view created by the two: select product.IDPRODUCT, sum(quantity) as totalOut, PRODUCTSTORAGE.DATAINPUT, ...
2
votes
1answer
40 views

Query to flatten schema

I have the following tables and columns: Users id | other-non-important-columns Containers id | Users_id | other-non-important-columns Content id | Container_id | other-non-important-columns ...
1
vote
0answers
29 views

SQL 2008 R2 Agent stopping sp_who2 running and can't view database or Agent properties

We're experiencing an unusual issue with SQL 2008 R2 SP2 (10.50.4297) where the SQL Agent had stopped but would not restart (this has been fine for months). After investigating the issue we had to ...
1
vote
1answer
25 views

How to get row count from all tables of a schema ( without using information schema )

The query should collect data from table name , schema name from information.schema and row count should be taken from actual table.
0
votes
0answers
206 views

Oracle - Slow queries without prepending schema name or providing hint

I am logged in as the schema owner in Oracle 11gR2 on Linux. I have 55 million rows in table. select max(col) from table; - takes 300 seconds (index full scan) select max(col) from schema.table; - ...
12
votes
2answers
540 views

SQL Server 2008 Performance issue with very strange resolution

I'm a long time DBA (12 years in SQL). I'm running SQL Server 2008 Enterprise in a Win 2008 clustered environment. 128gb memory and 32cpu in each cluster node. Not wimpy. I've got the weirdest ...
0
votes
1answer
186 views

SSIS Dataflow Task issue, moving data from SQL Server 2008 to MySQL via ADO.Net

Can you please help me in getting this problem solved.. I'm trying to build a SSIS package where I'm moving the data from SQL Server 2008 to MySQL. However I'm getting a weird problem in dataflow ...
0
votes
0answers
26 views

Need some help building a query to get info from several tables

I have this semi-complex table structure: And I need to return this data: { "id": "10111001", "rep_id": "30000001", "targets_id": "60011001", "brands_id": "10010001", "brand_name": ...
0
votes
0answers
38 views

How can I calculate the difference between my time column in seconds? [closed]

I have got a large database, one of the columns is the time with this format "08:27:22" and I am looking to find out the difference of seconds between the "open doors" and "close door" events. The ...
2
votes
3answers
67 views

SQL actually executed as planned in ORACLE?

I wonder if SQL is definitely executed as execution plan. I mean.. is the actual SQL execution process always consistent with execution plan, i.e. does the same SQL always give the same plan?
1
vote
1answer
240 views

I need advice on these queries

could you help me optimize these queries? here are queries, please note that you see something like OR 1=1 OR those are values I pass via php and may change. query#1: SELECT posts.status, ...
10
votes
3answers
124 views

Combining separate ranges into largest possible contiguous ranges

I'm trying to combine multiple date ranges that may or may not overlap into the largest possible contiguous date ranges. For example: Data: CREATE TABLE test ( id SERIAL PRIMARY KEY NOT NULL, ...