A core SQL statement, SELECT retrieves data from one or more tables or other sources of row set data such as views or table-valued functions.

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2
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3answers
75 views

Platform independent select ordered by primary key

Is there a reasonably standard way to perform a select on a single table and have the result set ordered by primary key without having to specify the primary key condition explicitly? Ideally I wish ...
-1
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2answers
100 views

Fetching Recently added rows from table [closed]

I have the following table structure , name || description || timestamp varchar varchar date time stamp column consists of time the row is added Now i need to fetch the ...
-2
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1answer
341 views

How to prevent duplicated records when applying ORDER BY NEWID() to fetch them randomly? [closed]

I tried using the solution provided in http://stackoverflow.com/questions/1117761/sql-query-to-return-rows-in-random-order to fetch random records in my query. But I have to add NEWID() to the list of ...
2
votes
2answers
336 views

Why does MySQL fail to use an index effectively when LIMIT offset is large?

I do not understand when querying 5 rows from a table of 500,000 rows, the following query takes 0.00sec: SELECT id, username FROM Users FORCE INDEX (PRIMARY) ORDER BY id LIMIT 20,5; But querying ...
0
votes
2answers
305 views

Select * on inner join with common columns

I have 3 tables (mysql db) on which I want to do an inner join. The problem is that these tables have common columns. I know I could use aliases to differentiate them (select A.x as Ax, B.x as Bx, C.c ...
1
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2answers
79 views

Not able to produce table based on conditional select

I would like to achieve something that probably ends up in some kind of conditional select (MS SQL) but I do not know how to. I have tried to simplified my problem to the description below: I have 3 ...
0
votes
3answers
127 views

How to query for 'First showed up as'

Given the following table: Date Trd (INT(10)) Code (VARCHAR(10)) T-Date 1-Jan-14 1 B 1-Nov-13 1-Jan-14 2 B 3-Oct-13 ...
2
votes
1answer
358 views

How can I use running total aggregates in a query to output financial accumulations?

I am attempting to write a query that will be consumed by a SSRS 2012 report. Given a paid invoice, with a certain set of account allocations towards which the money paid towards it must be saved, I ...
1
vote
1answer
303 views

Slow running query with inner SELECT in where clause

I have a query that looks like the following: USE DATABASE3; GO SELECT t1.COL1 AS COLUMN1, t2.COL2 AS COLUMN2, t1.COL3, t1.COL4 AS COLUMN4, t1.COL5 AS COLUMN5, ...
1
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0answers
116 views

How to join the tables in mysql to get wall messages and comments with name of person ? Only user and his friends messages

I have four tables in my mysql database as shown in the image url provided. I want to select data from the tables without duplication. I want to show messages and comments on wall according to the ...
2
votes
1answer
243 views

Search a Redis Database

Imagine having a tun of hashes in a Redis Database, each representing a user object. How would you get the user with for example the lowest registration date? The user where ts_registered is the ...
0
votes
1answer
710 views

How can I search a column in MySQL containing unix timestamps with a query referencing a different format?

I have a mysql table that contains something like: +-------------+-----------------+ | FOO1 | FOOTIME | +-------------+-----------------+ | blah | 1234567890000 | ...
0
votes
1answer
45 views

Order result by number of occurence of a word in a text

I am working with sqlite3/python . I would like to order results by the number of occurence of %@% in text. For exemple Jimmy 10 // Jimmy wrote 10 strings like %@% James 2 Sophia 0 ..etc The ...
1
vote
1answer
89 views

How to calculate average of list of qualifications of each pupil MYSQL

I have this database and query: http://sqlfiddle.com/#!2/b4cf72/116 And I would like to add a column with the average of the exam qualifications. However, I try doing this but it tells me there are ...
3
votes
1answer
143 views

postgres filtering select based on combination of joins

I am having trouble filtering a request that depends on a combination of child elements (one-to-many relationship) Please consider the following example. CREATE TABLE sample_container ( id serial ...
1
vote
1answer
721 views

How do I query for leaf nodes in a hierarchy using a closure table?

I have some hierarchical data (representing musical instruments and playing techniques), where each leaf in the hierarchy is an audio file. The nesting depth of leaf nodes will vary because some ...
7
votes
1answer
6k views

Autoincrement primary key in CREATE TABLE … AS SELECT

I created table using a complicated select query via CREATE TABLE ... AS SELECT.... How can I add an autoincrement primary key in this query? For example: create table `user_mv` select ...
1
vote
1answer
51 views

SELECT showing two COUNTs

I had this table: tblA id | name | value 1 nameA 1 2 nameA 0 3 nameB 0 4 nameC 0 5 nameC 1 6 nameC 1 As you see, Value can be 1 or 0 I need to perform a query ...
0
votes
1answer
169 views

How to remove duplicates in col1 and get group MAX in col2? / mysql

Given the following table: col1 Col2 A 1 B 1 C 1 B 2 B 3 A 0 C 5 how do I write a SELECT query (I just assumed has to be SELECT) that returns the unique items of col1 and the ...
0
votes
1answer
164 views

How to UPDATE MAX and MIN of a GROUP BY?

I have a SELECT query of a table with GROUP BY id col1 category 1 some 1 2 x 1 3 another 1 4 x 2 // should be removed 5 some 2 6 x ...
-2
votes
1answer
97 views

how to count result set for select statment [closed]

I have to make query from DB. I found some solution but it isn't so precise as it need to be. Here result of my query: country weight Germany 1687.5 Gt.Britain 1687.5 Japan ...
1
vote
1answer
158 views

Need to optimize simple SELECT query for InnoDB table with 2million rows

I'd like to make this query the fastest possible, since it's called really often. SELECT login_events.id FROM login_events WHERE ( DATE(created_at) >= DATE(CURRENT_DATE) AND person_id = 1 ) ...
0
votes
1answer
85 views

Get all items from list table which don't have a successful log entry for 'sent' in log table

How might one retrieve items that when joined either don't have a specific field (sent), or if they do have that field (sent) then they have an additional field (failure_reason) as well for every sent ...
0
votes
3answers
87 views

prepared statements are not inserted

i am new to JDBC and trying following code. Could not find the error in it try{ Connection con = ConnectionProvider.getCon(); stmt=con.prepareStatement("insert into ...
0
votes
0answers
1k views

SQLite UPDATE two tables from VIEW or TEMPORARY TABLE

Here is the query that doesn't compile just to show how it should look like. But since I can't do Multiple table UPDATE's. This fake query should be able to run the inner UPDATE's for both tables if ...
0
votes
1answer
41 views

Should the value of a select max be indexed when the where clause is already indexed

I have a customer_orders table in a schema designed to be shared between multiple companies. Each customer_order has an invoice number that should always start at 1 and increment based on company ...
2
votes
3answers
714 views

How to query efficiently from Postgres to select special words?

Let's say that I have a table called words with very many records. Columns are id and name. In the words table I have for example: 'systematic', 'سلام','gear','synthesis','mysterious', etc. NB: ...
1
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1answer
2k views

Select next and previous rows

I have the following table: CREATE TABLE post ( id bigint primary key, thread_id bigint, is_notice boolean, title text, content text ) I display the list ...
0
votes
0answers
96 views

How to grant privileges for a user to create views on specific tables on Oracle SQL?

I just added: GRANT CREATE VIEW TO user1; But it gives user1 access to ALL the tables, I would like them to only have access to the tables where the field X is user1
1
vote
1answer
240 views

INSERT INTO selected columns creates new column from JOIN [closed]

I have an INSERT INTO ... SELECT.. query that uses a JOIN on two tables. The results of the query should take a subset of the information and insert it into an existing table. That part works, but the ...
0
votes
1answer
156 views

Update , Select and Join using 3 tables

There are 3 tables: Label (Label_ID,Label_Name), Label_ID is Primary Key. Tracks (Prefix, Label_ID), Prefix is Primary Key,Label_ID is empty column Top100 (Prefix,Label) No keys in this table. My ...
1
vote
1answer
78 views

Mysql with index [closed]

I have this following sentence: SELECT Day(C.DataCadastro) AS Dia, Month(C.DataCadastro) AS Mes, Year(C.DataCadastro) AS Ano, COUNT(I.Plano) AS Total FROM clientes AS C ...
1
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1answer
4k views

Selecting multiple columns from multiple rows in one column (subquery?)

I'm working with MySQL 5.1.68. I have a situation where I'd like to select rows from another table into a column. I'd like to output this: id # name # citizen_name (multiple citizen names) 1 # ...
1
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1answer
171 views

I would like to query a range of criteria on multiple columns in MySQL

I have 3 columns in a mysql table. I'm using Innodb engine. I want to be able to search for some values on those columns and also anything close to those values. For example : We have 3 columns as ...
2
votes
1answer
3k views

MySQL query to evaluate ranges in date and time elements of a datetime column separately

TABLE EventID, EventTime (DATETIME) 1 2013-09-29 23:55:00.0 2 2013-10-01 00:05:00.0 3 2013-09-29 23:55:00.0 4 2013-09-29 23:45:00.0 5 2013-10-02 23:05:00.0 6 ...
9
votes
3answers
2k views

Why do I have to select from the dual table?

This works in the major Relation Database Management Systems most likely to appear on StackOverflow/dba.stackexchange, being SQL Server, MySQL, PostgreSQL and SQLite (WebSQL). select 'abc' abc, 1 ...
0
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0answers
298 views

How to increase MySQL performance with joins

I have a MySQL database with InnoDB engine. Particularly one of my queries became very slow. The query is shown below: SELECT t1.`ARTREF1` FROM `lijnen` AS t3 INNER JOIN (`kortingen` AS t2, ...
0
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1answer
416 views

How to avoid duplicate entries with SELECT statement?

+----+----------------------+---------+---------+---------------------+-------+ | id | translation | id_word | id_user | added | tuser | ...
-2
votes
1answer
116 views

How big the database should be in order to take 30 minutes to query

We have few tables each containing 2,5 million rows in average. Then there is a select query with joins. It takes more than 30 minutes to execute. The db server runs on a machine with 9GBs of RAM and ...
0
votes
1answer
532 views

SQL output formatting

I want this: "ACCOUNT_ID","MAJOR_VERSION","MINOR_VERSION","COUNTRY","ACCEPTANCE_TIMESTAMP","AGREEMENT_ID" "abcdefgh-1234-5678-ijkl-mnopqrstuvwx","20110901","1","CN","1329574013737","tos" But I get ...
1
vote
2answers
778 views

How to use OR in query with priority?

In a simple query like SELECT * FROM table WHERE id='x' OR id='y' How to give a priority to get only one of the WHERE clauses? I mean getting rows with id='x'. Only if there is no row, get row ...
1
vote
1answer
3k views

How to run a SELECT query within while loop in PHP?

Within a SELECT query via PHP while loop, I need to run a mysql SELECT query as $result1 = $mysqli->query("SELECT * FROM table1"); while ( $row = $result->fetch_assoc() ) { if ( $row['X'] == ...
3
votes
1answer
242 views

Combine - Select Into, with Insert Into Select

I've read many explainations like this one here that say "Select Into ..." is to create new tables and "Insert Into ..." is to append to existing tables. I'm automating a coworker's sql scripts. ...
2
votes
1answer
2k views

Postgres nested hstore select query

I have a carts table with items hstore column. An example entry in this column is: carts.items row#1 = { "1614" => {:quantity=>"100", :price_cents=>1655}, ...
0
votes
2answers
71 views

Difference between the given queries

I am required to retrieve the list of pno ( product_id ) for the products which were purchased by two customers. For this, I have been given two relations which are ( along with the attributes ) as ...
0
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1answer
2k views

How to create an Sql table from SELECT with a multiple row DISTINCT constraint?

I want to create a table from a SELECT statement based on a multiple row DISTINCT, but PostgreSQL does not allow me to do it. I need to create a table where the elements were previously selected from ...
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votes
1answer
5k views

Delete from table where multiple fields match select subquery from other table

I want to delete an entry in a table where multiple fields match the results of another select subquery which takes data from another table. This is what I have so far, though it doesn't work: ...
1
vote
2answers
7k views

Index for date column for range query in Oracle?

We have a lot: select count(*) from TBL where XDATE between ? and ? and FLD = ?; We expect to boost performance by tuning index on XDATE column (which have DATE type). What type of indexes more ...
2
votes
1answer
363 views

Help with SELECT queries

I need help with some queries. I struggled do find out how to do it, but I think I finally caught on or at least got the results I was looking for in the database. These are the tables (given by my ...
1
vote
1answer
55 views

Altering strings while selecting them

I'm working in SQL Server 2008, I have a varchar(255) column in my table, I want to select out all of the strings which contain the ':' character, and select the first part of the string before (but ...