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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How to add additional tables/fields into a query with multiple inner joins?

Given this query (many thanks to RolandoMySQLDBA from question Select records that do not have associations outside a certain list), how do I add other fields from other tables into my result? SELECT ...
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961 views

Insert from one row to another using cases

My original table was(being used since 2005): CREATE TABLE `request` ( `msg` VARCHAR(150) NOT NULL, `id` VARCHAR(20) NOT NULL, `ctg` VARCHAR(10) NOT NULL DEFAULT 'misc', `date` ...
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223 views

MySQL SELECT query: i want show duplicated entries

Example My query is: SELECT code_CAT FROM categories WHERE id_code IN(14,14,14,14); output is: 53724 Only one row. Instead I want this output: 53724 53724 53724 53724 How can I achieve ...
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961 views

How to change the display of an empty string in mysql command line tool?

I'm maintaining a database with InnoDB tables. These tables have some columns of type (from show create table): `val0` varchar(30) default NULL, `val1` varchar(30) default NULL, etc... From the ...
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165 views

Complex mysql selection

I have the following table, id | booki_id | bet_id | bet | bettype | line | odds 1 | 123 | 321 | 1 | 3way | 0,0 | 2.3 2 | 123 | 321 | 2 | 3way | ...
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“For each group of results fullfilling condition X, select only result with smallest column value A”

I have a table with data and dates like so: DECLARE @p TABLE (P_key int, P_Data char(1), P_ValidUntil datetime) INSERT @p VALUES (20, 'T', '2003-02-28') INSERT @p VALUES (21, 'U', '2005-05-31') ...
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MySQL Count rows from another table for each record in table

SELECT student.StudentID, student.`Name`, COUNT(attendance.AttendanceID) AS Total FROM student LEFT JOIN attendance ON student.StudentID = attendance.StudentID I am trying to count the last ...
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36 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 ...
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469 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 ...
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137 views

Select statement for selecting every week's log record

Here is a simplified version of the table in question: +------------------------------------------------------+ | DatabaseName | LogRecordNumber | LogTimestamp | ...
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178 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 ...
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41 views

Should I drop this column or is there a query that can achieve a results table without duplicate columns?

I use a column named active in several of my database tables to adjust whether a particular entry/row/user/etc should be included in future query result tables instead of deleting the information. ...
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214 views

Running queries directly on DB2 databases

Just have a general query, if it is really fine or safe to run long select queries on RDBMS production Databases specifically DB2? If NO, what are the major risks and issues in executing select ...
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818 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 ...
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331 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, ...
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270 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 ...
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5k 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 # ...
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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'] == ...
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393 views

Select records that do not have associations outside a certain list

I have a mySQL table of nodes and each node can be associated with many categories. I have a list of category ids that are acceptable (498, 499). I want to select only nodes who do not have ...
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185 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 ...
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334 views

How to re-arrange rows to best fit within groups?

I categorized a table with the method introduced here to categorize my items to folders with a limit size of 100. mixing_order id num_items cat order_in_cat cumulative_sum folder 1 ...
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2k views

How do I perform a UNION query on a dynamic list of tables?

My database has an unknown amount of tables, named with the same prefix followed by a random string: _ct_<random_string>. Each of these tables has the same data structure. I also have another ...
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73 views

How can I query to do this?

I have 2 tables, in feeds I have my feeds and (feeds.ID) is the primary key. second table is items. and feeds.ID is realted to items.feed_ID, so with a simple inner join i can extract the data of each ...
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276 views

Shift db data to another column

I have the following table id | ev_id | ev_loc_id | a | b | prev_a | prev_b If I the (ev_id AND ev_loc_id) not exist in the table then I just insert them, otherwise I'm putting ...
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how to cache a subset for cascading select queries in mysql

Here is another database problem I stumbled upon. I have a date-range partitioned MyIsam look-up table with 200M records and ~150 columns. On this Table I need to perform cascading SELECT-Statements ...
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37 views

Reference column alias in same SELECT list

I'm converting an old MS-Access-based system to PostgreSQL. In Access, fields that were made up in SELECTs could be used as parts of equations for later fields, like this: SELECT samples.id, ...
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52 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 ...
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40 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; ...
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115 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 -- ...
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57 views

Slow Query with LIMIT

We have this query: SELECT "messages".* FROM "messages" WHERE "messages"."account_id" = 1 AND "messages"."status" = 'unread' AND (created_at >= '2014-04-24 01:00:00.000000') ORDER BY id DESC It ...
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65 views

Select all foreign key relationship chains from any set of potentially gapped table names

I am using this query to find all foreign key relationships: SELECT con.relname AS child_table, att2.attname AS child_column, cl.relname AS parent_table, att.attname AS parent_column ...
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64 views

use variable to determine the name of a column in the select in postgre

I'm trying create a update for a new structure of tables from a old table, but not using functions. I'm trying create a script to it. The old table is like this: -- old table (OldTable) name| col_a | ...
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64 views

Selecting most recent date when dates are stored in another table

Working in a MySQL database, I have tables set up like this: Table song_instances has song_id (int), meeting_instance_id (int) The meeting_instances table has columns meeting_instance_id (int), ...
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65 views

Mysql: Problem using GREATEST with IFNULL and join

I have a query selecting the greatest value of 2 timestamp. To Achieve it I'm calling: SELECT GREATEST( IFNULL( tableb.create_time, 0 ) , IFNULL( tablea.create_time, 0 ) ) I'm using IFNULL because ...
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40 views

Multiple selects ordering desc from single table

I'm trying to do multiple selects to give multiple ordered columns. I'm struggling to get the below mysql query to achieve the output I want. SQLfiddle: http://www.sqlfiddle.com/#!2/a1002/3 ...
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SELECT, PROJECT, CARTESIAN PRODUCT and JOIN

I have the following tables; DOG +----------------------------------------------+ | Name Type Age Kennel_name Owner_name | +----------------------------------------------+ ...
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139 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 ...
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54 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 ...
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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 ...
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452 views

Merge 2 tables and fetch data one by one

I have two tables: product & offers. products has (prod_id, category_id, prod_name, brand, price, status) offers has (offer_id, prod_id, offer_type, discount_amt, validity) I want to display ...
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182 views

Get all comment.message, status.message, users.* and profiles.* where users.user_id exists in friend.friend_id or friend.user_id

I need some help building this query because it's a bit complicated at least for me. I need to get all comment.message, status.message, users.* and profiles.* where users.user_id exists in ...
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162 views

MAX (id) function with MySQli

How can I use the following statement to return only the record with the maximum PersonID from the table? /* Create the prepared statement */ if ($stmt = $mysqli->prepare("SELECT Max(PersonID) AS ...
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521 views

Can a RDBMS connect to a remote server, execute a select query and copy them into a local table just with SQL commands?

I'm sorry it may sound stupid but I've been wondering about how multiple databases are automated before the virtualization era. Can a DB Adminsitrator make a stored procedure to get data from a remote ...
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1answer
43 views

Work with table named Group [closed]

I have a table named Group in my database , when I try to work on it it gave error : SELECT GroupID,GroupName FROM Group it said : Msg 102, Level 15, State 1, Line 1 Incorrect syntax ...
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4k views

Postgres: How to insert row with autoincrement id

There is a Table "context". There is an autoincrement id "context_id". I am using sequence to retrieve the next value. SELECT nextval('context_context_id_seq') The result is: 1, 2, 3,...20.... But ...
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How to mix pairs of rows without JOIN (in a temporary table)?

I have a TEMPORARY table containing pairs of key/value as id col1 col2 type pair 1 key1 key2 key 1 2 value1 value2 value 1 3 key3 ...
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156 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 ...
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209 views

How to create an Access query to find # symbol into a field?

It seems easy but I'm missing something. I have a MySQL database that is connected from access through ODBC connector. I'm looking for the fields where there are # symbol but I'm getting zero ...
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3k 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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724 views

Retrieving a fixed range of rows from Postgresql

I have a query: select qid,ansid,ans from table1 where askerid='something' This query can retrieve many rows. But I want to display only 50 rows at a time and then if the user clicks on more, the ...