Combining multiple data points into a single data point. This usually is used in reference to SQL and usually to an aggregate function of some sort.

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390 views

I have multiple sources INSERTing into a MySQL innodb table. My periodic aggregation script never makes accurate aggregates. Why?

I apologize in advance if this is a repeat. I'm not really sure how to properly ask for what I'm running into. I have a large InnoDB table set up. I have 3 sources that all INSERT concurrently at a ...
2
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1answer
376 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 ...
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1answer
303 views

MongoDB: Aggregation workaround by helper collection

Since I regularly run against mongodb's document size limit and also aggregation framework's group limitations >16M, depending on the amount of data I need to process, I look for a simple workaround. ...
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1answer
605 views

Performing aggregations and calculations: SQL (CTE) vs MDX

I’ve hit a wall and would like some expert advice. I’m building a data warehouse and don’t quite understand whether the calculations (also time aggregations) should be done in SQL (T-SQL and CTE) or ...
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8k views

how to calculate difference of first row and last row fields value in each group

I have table with structure like this: +-------+------------------+ | Value | Date | +-------+------------------+ | 10 | 10/10/2010 10:00 | | 11 | 10/10/2010 10:15 | | 15 | ...
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3answers
4k views

Select query to retrieve values even if are null

I need some help in a query. Need to retrieve data from 1 table, even if one of the field has null value. Here's an example: Select name, SUM(credit) as credit From expenses Where name like ...
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692 views

LIMIT to one row per ID

This query gives me multiple hits because of each assetid may contain many vb.title. How can I limit the result to only 1 hit for each assetid? 'select DISTINCT v.id, v.purchasedate, ...
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4answers
4k views

Should I use the Infobright database or is there a better aggregation solution?

We are a MySQL front-end shop and have a system currently logging event data in a highly structured format. Think apache traffic log. We need to be able to aggregate counts of this data (cube) vis a ...
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108 views

Longest matching suffix while using aggregate functions

Background Looking to find the longest matching string suffix. Setup Consider the following fiddle: CREATE TABLE noun ("label" varchar(10)) ; INSERT INTO noun ("label") VALUES ...
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3answers
90 views

Can I perform a MAX over a pair of columns?

I would like to execute the following: SELECT person, MAX( (date, priority) ) FROM table GROUP BY person; It would return a person, date and priority row for each distinct value in the person ...
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731 views

Postgres error [column must appear in the GROUP BY clause or be used in an aggregate function] when sub query is used

I have two tables employee and phones. An employee can have 0 to n phone numbers. I want to list the employee names with their phone numbers. I am using the below query which runs fine. SELECT ...
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225 views

Split two rows into two columns

I have the following table: id | name | action | count ------------------------------ 1 | Value1 | 0 | 27 1 | Value1 | 1 | 49 2 | Value2 | 0 | 7 2 | Value2 | 1 | ...
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28 views

Is it possible to find the user whose aggregated score reaches X value first?

Given this sample fiddle containing sales value and date for two users: http://sqlfiddle.com/#!2/8148be/3 How can I find the first user who has reached a total saleValue of 30 since the beginning of ...
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2answers
68 views

Return counts for multiple ranges in a single SELECT statement

I have a Postgres database table foo that, among other things, has a column for score that ranges from 0 - 10. I want a query to return the total number of scores, the number of scores between 0 and ...
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56 views

Postgres Index a query with MAX and groupBy

Is there any way to index the following query? SELECT run_id, MAX ( frame ) , MAX ( time ) FROM run.frames_stat GROUP BY run_id; I've tried creating sorted (non-composite) indexes on frame and ...
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60 views

How group by affects aggregate functions

I tried to understand the following scenarios: Table name: family +------+-------+ | id | name | +------+-------+ | 1 | alice | | 2 | bob | +------+-------+ That table will be used for ...
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153 views

Aggregate function / query in Oracle 11g

I am working in Oracle 11g. I have been racking my brain all day trying to figure out how to write a particular SQL statement (am a Java/.NET Developer, would not consider myself a SQL expert) I ...
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38 views

Aggregating on a repeated group

In a current report, I'm trying to track the migration of a person from department n, to n+1, or to n+k. My data is split into a row per term (university data). An example: dept | term ...
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64 views

Combine results of two queries, where the second relies on the first

I have one query which is returning name(text), total, created_at And another query which is returning the same thing name(text), total, created_at The second query usually is returning more ...
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2answers
94 views

Understanding multiple table join with aggregation

I have a basic question on how JOIN works on multiple tables. I want to count occurrences of Foreign Key in link1 & link2 CREATE TABLE main ( id SERIAL PRIMARY KEY, name text NOT NULL ); ...
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1answer
54 views

Writing a view that caches to another table

I have a table market_trades with columns timestamp, market_id, and amount: api_production=# \d market_trades; Table "public.market_trades" Column | ...
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1answer
131 views

Fetch data from same table using two group by clauses in mysql

I have one table name as consultant with 4 fields(id, name,user_type, Created date). I need to write an mysql query for return the count of user_type in each month. In my table, user_type is ...
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77 views

Query for frequency of e-mail addresses in a field

Newbie here. I know the answer is out there, but lack the vocabulary to ask the right question... I am looking for a MYSQL query which gives me the frequency of addresses in the field emailaddress. ...
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280 views

Slow queries related to subqueries using aggregation

Here's a simplified version of the queries I am running: select ... from editions join edition_events on edition_events.edition_id = editions.id join events on events.id = ...
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1answer
619 views

ORDER BY on aggregate field on a closure table giving unexpected results

I am updating my companies product database and I'm looking into different ways to do design our faceted navigation "selector" tables. The idea of faceted navigation might look like this: It's ...
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1answer
43 views

Join and count boolean columns by logical OR

There are two tables: user_table and user_schedule. Each user has four schedule rows (one for each 6 hour period per day) with one column for every workday. The desired result is to count the number ...
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335 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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83 views

Optimizing for data that does not fit in memory

We have a database that contains around 235 GB of data (calculcated using pg_total_relation_size for each table) on a server with around 77GB of memory. The server is used for nothing else (aside from ...
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46 views

Multidimensional aggregates

Suppose one wanted to cache simple aggregate data over a table or grouped parts of a table, one could simply make a table with the aggregated results. If the original table is only appended to, it is ...
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1answer
54 views

Consolidating large table

I need some help with a complex query. Table def: Table "public.agent_log" Column | Type | Modifiers ...
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1answer
126 views

Retrieve title from rows with a maximum count in other columns

Given the following table archived: CREATE TABLE archived ( sid serial -- row id showurl text -- can be: btg, tmwwt, gcaf, emda title text reference text -- title id ...
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1answer
229 views

Get maximum from aggregated values in a query

I have a table details it has a column kills and a column player_slot and a column match_id. I want to find the maximum difference between the SUM of kills for player_slot 0-4 and 128-132. Can someone ...
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3answers
268 views

Aggregating data - Getting data inserted after last time query was run

On a SQL Server 2008 R2 DB, I'm running an aggregation query every hour or so, on data that's being constantly inserted into a table, and what I'd like to do is pull all the "new" records that were ...
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160 views

Mysql: Schema/Query Performance Approach for aggregated mailbox folders

I am about to code a messaging system where users can write messages to other users. User can create custom inbox folders for sorting the messages they receive, however, every user has 2 main inboxes: ...
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275 views

Group activities in activity feed by users and products

On my website I'm building an activity feed where I got the basics done and are now making some improvements here and there. One of them is the grouping. I've built it so that if multiple users buys ...
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1answer
100 views

How to aggregate datapoints in a table?

Suppose I have following table - CREATE TABLE data_points (t DATETIME PRIMARY KEY, value INTEGER); I want to aggregate the data by calculating average of every 10 points in the table. i.e. If ...
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1answer
49 views

Grouping() equivalent in PostgreSQL?

I have a SQL query that runs in MS SQL Server and it has grouping(), rank() and rollup() functions / keywords in it. The query is given below. How can this be translated to PostgreSQL? select top ...
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43 views

Combine multiple similar queries into one

I need to calculate a weighted average using the following table. I have to calculate this number for metric_1 up to metric_10. All the metric columns have a value from 1 to 5. ...
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2answers
73 views

Calculating percentage from two tables

I have two tables: First one contains unique mentees under one mentor, so mentors can have more than one mentee in that table. Second one contains interactions of mentors with mentees on different ...
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1answer
47 views

How to properly aggregate?

I have a table for logs with over 6 million records. I want a query that shows me all the occurrences where the src goes to the same destination/port. I tried this: SELECT src, dst, dstport, ...
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64 views

Pentaho Kettle (Data Intergration) MongoDB Aggregation

I'm using kettle v5.2 which support the aggregation pipleline in MongoDB when using MongoDB input the query works for small data set but I need to use option allowDiskUse to the query can't figure ...
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1answer
73 views

MongoDB Insert Performance

I have some data which are aggregated in chunks and later pushed into another collection. The problem is that aggregated data pushing to another collection is very slow and takes from few hours and i ...
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1answer
73 views

Select two aggregate functions on the same column using different criteria - performance

Dear stack exchange users, first question here. The database in question is a service database where a user hires a service. Now I would like to show the person that was hired an overview of how many ...
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65 views

ORA-00937 when calculating a sub-value in an aggregate select statement

The problem described below applies to Oracle 11g databases. I also tested the statements on MySQL and PostgreSQL with no problems of the kind mentioned in this question. I want to use an ...
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1answer
315 views

Calculating a running balance to store with transactions

I need to put a read-only copy of balance and transaction data from a legacy system, which will only be used to view/print statements. Balance | id | member_id | product_id | balance | | 1 | ...
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130 views

Multischema view for postgres , querying multiple databases

Im managing SaaS app where each customer has a separate database (Postgres 9.3) . I need to figure out the best way to aggregate and query this data ( READ-only ). I know postgres has problems with ...
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85 views

Join and aggregate result and insert blanks for missing appendants

Consider these two simplified tables: CREATE TABLE "sources" ( "id" serial NOT NULL, "name" text NOT NULL, CONSTRAINT "sources_pkey" PRIMARY KEY ("id") ); CREATE TABLE "values" ( ...
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1answer
589 views

SQL hourly data aggregation in postgresql

I am a newbie with database so I'm seeking your help with this one. I have a table containing time series data. 2012/01/01 00:10, 10 2012/01/01 00:30, 5 2012/01/01 01:00, 10 2012/01/01 01:40, 10 ...
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88 views

Type with nested table in oracle

I want to create a type with a nested table. I have a table called assignment_tbl which I want to put a type assignment_status. This assignment_status contains primitive types but also contains a ...
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347 views

How to aggregate pairs of id values into groups

I have a table with two id columns id1 and id2. Each row shows that 2 id values have been linked together. My actual data has both id columns as varchar(20) but I have used integers in the example ...