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.

learn more… | top users | synonyms

0
votes
1answer
24 views

Padding MySQL queries

I'm trying to retrieve logs of our plant where a certain event has occurred. At the moment, I can query the actual event by using an alarm_code field. However, I'd also like to include about an ...
0
votes
1answer
67 views

Alternatives to Linked Servers (Allow Inline SQL with Parameters)

I am trying to find a solution to execute inline SQL with parameters against some liked server databases. From what I have found online the only proper way to query a linked server is to use ...
0
votes
0answers
42 views

What is the difference between normal Select query and a Select query inside Common Table Expression(CTE)? [duplicate]

I'm having a table 'Products' and if Execute this query SELECT TOP 1000 [ProductID] ,[ProductDesc] ,[ManufacturingDate] ,[ExpiryDate] ,[Price] FROM ...
10
votes
4answers
3k views

Benefits of using backtick (`) in MySQL queries?

In MySQL we can create queries with or without the backtick (`) symbol. Example: SELECT * FROM TEST; SELECT * FROM `TEST`; Both works fine in mysql-console. Is there any technical difference ...
0
votes
1answer
43 views

Slow query while selecting a higher offset from millions of rows

I have sort of security log files containing millions of rows. On my current testing I imported the data for one month which is the sum of ~14,000,000 records. The table contains several set of fields ...
0
votes
1answer
208 views

Select rows from table where each row refers to a different schema

I have customer table in public schema. And I have a schema named after each customer. Each customer schema contains different tables like portals, plugin, ... When I want to select portals used by ...
0
votes
0answers
34 views

How to fetch data on a single column from a table having composite key [duplicate]

I am working on a messaging application, where the users can have a group conversation with multiple recipients. So in my database, I have a table called user_message where user_id and message_id is ...
0
votes
2answers
51 views

Searching a database safely using SELECT

I have a site that allows users to search the database for several items. However I am not that good with SQL and I have read that allowing user to type in boxes that then use "SELECT-statements" is ...
2
votes
1answer
170 views

Search within same ID across several rows

My table has the following structure: +----+---------+------------+-------------+ | id | word_id | meaning_id | sentence_id | +----+---------+------------+-------------+ | 1 | 1 | 15333 | ...
2
votes
3answers
437 views

How to speed up a multiple select query

EDIT - Putting my whole stored procedure: I have the below stored procedure: CREATE PROCEDURE [dbo].[data_Update] @Owner NVARCHAR(255), @ID VARCHAR(255), @Division VARCHAR(255), @Manager ...
7
votes
2answers
20k views

SELECTing multiple columns through a subquery

I am trying to SELECT 2 columns from the subquery in the following query, but unable to do so. Tried creating alias table, but still couldn't get them. SELECT DISTINCT petid, userid, (SELECT ...
0
votes
0answers
59 views

SELECT from Function that return CURSOR

I would like to select from a function that return a SYS_REFCURSOR Type value. for example : CREATE OR REPLACE FUNCTION my_funtion ( my_param IN VARCHAR2) RETURN SYS_REFCURSOR IS ...
0
votes
2answers
56 views

How to split a row in a result into mutliple rows

I have the following query: SELECT vs.MonthName AS Month, vs.Region, vs.Category, CAST (MIN (a.TotalAmount) AS money) AS ActualAmount, MIN (a.TotalCases) AS ...
1
vote
1answer
62 views

How to insert the gathered dates into another table using INSERT SELECT in MySQL?

insert into rfdate (date) select adddate('1970-01-01',t4*10000 + t3*1000 + t2*100 + t1*10 + t0) selected_date from (select 0 t0 union select 1 union select 2 union select 3 union select 4 union select ...
0
votes
0answers
31 views

Use join to aggregate data from various normalized tables

I have a database as follows: tbl_clients (Primary Key: client_id, Foreign Keys:place_id,district_id,zone_id,country_id) tbl_places (Primary Key: place_id) tbl_districts (Primary key: district_id) ...
26
votes
1answer
3k views

USING construct in JOIN clause can introduce optimization barriers in certain cases?

It was brought to my attention that the USING construct (instead of ON) in the FROM clause of SELECT queries might introduce optimization barriers in certain cases. I mean this key word: SELECT * ...
0
votes
0answers
21 views

Need help on transferring data from a PostgreSQL database to a future (to be decided) database!

(English isn't my native language) I'm doing an internship for school and my task is to theoretically describe the best way to transfer the data from their current database (PostgreSQL) that they have ...
0
votes
1answer
39 views

select statement for subtype

Okay, so all I'm trying to do here is list the managers who supervised the employee that charged a customer $100 for a rental on November 1st, 1998. My issue is that I don't know how to select the ...
0
votes
1answer
89 views

Update does not working while select returns right results

I am trying to execute the query below: UPDATE( SELECT Ord.Completed FROM Product P INNER JOIN Order1 Ord ON Ord.OrderID = P.OrderID WHERE EXISTS( SELECT * FROM Delivery ...
5
votes
1answer
3k views

SELECT with large WHERE IN clause taking long time

I'm pretty new at all this so be gentle :). I have large medical DB where I need to extract data for patients based on selected doctor(s). Right now I build a patient list by SELECT patID FROM ...
0
votes
1answer
22 views

How to modify the below script to take tables and its sizes for a particular databse to send via mail to a recipient?

SELECT top 10 t.NAME AS TableName, (SUM(a.total_pages) * 8)/1024.0/1024.0 AS TotalSpaceGB FROM sys.tables t INNER JOIN sys.indexes i ON t.OBJECT_ID = i.object_id INNER JOIN ...
0
votes
1answer
102 views

How to make a single row result query to return multiple rows

I have the following WITH SQL Query which does select a set of filling stations along a route within the distance of 1000m. To have the measurement in meter I cast the geometries to geography. I also ...
0
votes
2answers
132 views

How to find all schemas where a table has records?

In my Oracle database, I have a number of schemas (users/owners) with similar table structures (about 100 in total). However, some tables are empty in a lot of schemas. Is there a way to find out for ...
2
votes
1answer
133 views

MySQL - Get Minimum Value, Data From Multiple Tables

Good evening all, first post on the DBA forums. I am having real issues working out how to accomplish a seemingly simple task within MySQL as a model for PHP code later on. I am not exactly a MySQL ...
0
votes
1answer
49 views

4 tables, find department with the highest average salary [closed]

ABC is an organization operating in a certain country. Below are the data for the database that manages the information on this organization's employees: employee(employee_name, street, city) ...
0
votes
1answer
18 views

Selecting one variant out of different similar results

I have a table that looks as follows: Book Format Contents A html ... A markdown ... B html ... C markdown ... I want to return only 1 version of a book. ...
1
vote
0answers
41 views

How to use the value from record like as varchar?

I'm trying update a old table with result of selec for another tables but get a error using this sintaxe (e.g.): DO $$ DECLARE _roles refcursor; _onerole varchar; _record RECORD; ...
0
votes
2answers
34 views

Get all the users that are managed by a targeted manager

I have the following model: Table user: (id, name, direct_manager_id) Table customer: (id, name, managed_by_id) i.e. users can have another user as their direct manager, Customers can be managed ...
1
vote
1answer
38 views

Creating a View with results from join of scalar tables

I am really bad at SQL Queries and seem to be stuck at a very odd problem. Maybe there's an alternative of doing this, but I simply can't figure it out. Maybe you guys can help! So, here's my ...
2
votes
2answers
2k views

To select from all tables inside the schema in PostgreSQL

Is it possible to select from all tables inside the schema? I got all the table names from select table_name from information_schema.tables but I am unable to use it to do my query.
0
votes
1answer
48 views

Need help in incrementing the date in oracle

Error thrown as "Invalid number" while trying to increment the date. Given below is the query executed through sqlplus. Please help me on this. select ''''||to_date(:To_date, 'dd-mon-yyyy')+1||'''' ...
10
votes
2answers
6k views

How to select specific rows if a column exists or all rows if a column doesn't

I'm writing a script that gets a count of rows for a few tables, however for some tables I want to only get a count of rows where a flag is set (in this case active=1). Is there a way I can do this ...
2
votes
1answer
180 views

How to speed up slow query using GROUP BY and CASE?

I'm not very experienced with MySQL and and trying to figure out how to speed up a slow query using GROUP BY and CASE statements. CASE 1 -- GROUP BY and CASE SELECT SQL_NO_CACHE m.id, m.sku, ...
1
vote
0answers
123 views

two column compare ,get count(*) of two column A value same cloumn B value

I have a Mysql table as --------------------- -- page - user -- --------------------- -- page a - user 1 -- -- page a - user 2 -- -- page a - user 3 -- -- page b - user 1 -- -- page b - user 3 -- ...
0
votes
1answer
344 views

Select into existing table where ID is in another table [closed]

I have one table containing ~35k IDs (TableC), one table that features multiple columns (TableA), amongst others the ID from the before mentioned table and a third empty table, featuring the same ...
0
votes
1answer
19 views

Copy every entry from TableA to TableB where the ID is in a textfile containing a list of IDs

I have a text file (or an xls) with a 35k lines, each containing a single ID. I'm required to copy every entry of TableA to TableB where the ID is in said list. Would it be best if I'd create a new ...
0
votes
1answer
82 views

using update query with subquery in Oracle sql

I have an update query where I am trying to update a field but for more than one record, I am trying a join but it doesn't work. Below I get multiple values that come back from the select statement ...
1
vote
3answers
2k views

`Select` query take more time than it should

I have a MySQL database table with nearly 23 million records. This table has no primary key, because nothing is unique. It has 2 columns, both are indexed. Below is its structure Below is some of ...
-2
votes
1answer
14k views

How to get MAX and MIN in GROUP BY query?

In a simple query SELECT col1, col2, col3 FROM table1 GROUP BY col1 each row includes the first value of col2 and col3 for each unique value of col. How to select MAX and MIN for each value of ...
3
votes
3answers
20k views

Getting SELECT to return a constant value even if zero rows match

Consider this select statement: SELECT *, 1 AS query_id FROM players WHERE username='foobar'; It returns the column query_id with value 1 along with a player's other columns. How would ...
0
votes
1answer
45 views

How not to display column name during select query

I have a sql file which prints the count(*) of some tables and result of it is something like this. COUNT(*) ---------- 10443 COUNT(*) ---------- 497 COUNT(*) ---------- ...
0
votes
0answers
34 views

SSRS using select from (Select)

I want to report a script which contains a Select from (Select), when I just run the second select I have no problem but when I put the whole script it loads and nothing happens. Here's my code : ...
0
votes
1answer
215 views

Columns count in SELECT query and SQL Server buffer cache

Let's assume that I have a table with 30-50 millions records. It has ~40 columns. Currently when I request data it always requests all columns because of legacy ORM that we use. I know that if we ...
0
votes
1answer
39 views

Move/Copy unique entries only from TableA to TableB, if it's not in the destination table

I'm required to move every unique entry from TableA to TableB, it the unique entry from TableA is not already in TableB. Both tables look the same, they don't have any keys, but the combination of to ...
0
votes
1answer
87 views

Select all results from two independent tables

I have two tables: Comments -------- id comment_content time_stamp Activities ----------- id activity_content time_stamp And I would like to combine the results from both, ordered by their ...
2
votes
2answers
58 views

How can I simplify this UNION?

Here's the case - I have the following query: SELECT DISTINCT post_id FROM ( ( SELECT DISTINCT rp.post_id, pm.meta_value AS premiere_date FROM wp_related_people AS rp JOIN ...
0
votes
1answer
221 views

Mysql Select table records which have not been updated since last month

I have a table names 'scoredata' having fields id, lessonid, levelid, studentid, addedate in which score for each day will be entered by the admin. I want to select only those studentid whose score ...
1
vote
3answers
583 views

Select only rows with minimum values from union table

SQL Server 2005 Here is a sampling of the data from a union of two tables (named "vProducts_All"): DBID UPC Price1 Price2 1 023614025559 689.0000 649.0000 2 ...
1
vote
1answer
207 views

Determine last time a mysql table was accessed (i.e. SELECT'ed)

In my mysql DB schema there are old tables that are no longer used. I want to come up with a systematic way to show my developer a list of tables and last time they were read (SELECT'ed, not ...
0
votes
1answer
149 views

Copy Data To Different Server using SELECT * INTO?

I'm not a DBA by any means. I'm just knowledgeable enough with the MySQL command line to be capable half the time and dangerous the rest. Today I was working on exporting data from a one DB into ...