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Hive provides SQL type querying language for the ETL purpose on top of Hadoop file system.
Hive Query language (HiveQL) provides SQL type environment in Hive to work with tables, databases, queries.
We can have a different type of Clauses associated with Hive to perform different type data manipulations and querying. For better connectivity with different nodes outside the environment. HIVE provide JDBC connectivity as well.
Hive queries provides the following features:
Data modeling such as Creation of databases, tables, etc.
ETL functionalities such as Extraction, Transformation, and Loading data into tables
Joins to merge different data tables
User specific custom scripts for ease of code
Faster querying tool on top of Hadoop
In this article, you will learn-
Creating Table in Hive
Before initiating with our main topic for this tutorial, first we will create a table to use it as references for the following tutorial.
Here in this tutorial, we are going to create table “employees_guru” with 6 columns.
From the above screen shot,
We are creating table “employees_guru” with 6 column values such as Id, Name, Age, Address, Salary, Department, which belongs to the employees present in organization “guru.”
Here in this step we are loading data into employees_guru table. The data that we are going to load will be placed under chúng tôi fileOrder by query:
The ORDER BY syntax in HiveQL is similar to the syntax of ORDER BY in SQL language.
Order by is the clause we use with “SELECT” statement in Hive queries, which helps sort data. Order by clause use columns on Hive tables for sorting particular column values mentioned with Order by. For whatever the column name we are defining the order by clause the query will selects and display results by ascending or descending order the particular column values.
If the mentioned order by field is a string, then it will display the result in lexicographical order. At the back end, it has to be passed on to a single reducer.
From the Above screen shot, we can observe the following
It is the query that performing on the “employees_guru” table with the ORDER BY clause with Department as defined ORDER BY column name.”Department” is String so it will display results based on lexicographical order.
This is actual output for the query. If we observe it properly, we can see that it get results displayed based on Department column such as ADMIN, Finance and so on in orderQuery to be perform.
Query :SELECT * FROM employees_guru ORDER BY Department; Group by query:
Group by clause use columns on Hive tables for grouping particular column values mentioned with the group by. For whatever the column name we are defining a “groupby” clause the query will selects and display results by grouping the particular column values.
For example, in the below screen shot it’s going to display the total count of employees present in each department. Here we have “Department” as Group by value.
From the above screenshot, we will observe the following
It is the query that is performed on the “employees_guru” table with the GROUP BY clause with Department as defined GROUP BY column name.
The output showing here is the department name, and the employees count in different departments. Here all the employees belong to the specific department is grouped by and displayed in the results. So the result is department name with the total number of employees present in each department.
Query:SELECT Department, count(*) FROM employees_guru GROUP BY Department; Sort by:
Sort by clause performs on column names of Hive tables to sort the output. We can mention DESC for sorting the order in descending order and mention ASC for Ascending order of the sort.
In this sort by it will sort the rows before feeding to the reducer. Always sort by depends on column types.
For instance, if column types are numeric it will sort in numeric order if the columns types are string it will sort in lexicographical order.
From the above screen shot we can observe the following:
It is the query that performing on the table “employees_guru” with the SORT BY clause with “id” as define SORT BY column name. We used keyword DESC.
So the output displayed will be in descending order of “id”.
Query:SELECT * from employees_guru SORT BY Id DESC; Cluster By:
Cluster By used as an alternative for both Distribute BY and Sort BY clauses in Hive-QL.
Cluster BY clause used on tables present in Hive. Hive uses the columns in Cluster by to distribute the rows among reducers. Cluster BY columns will go to the multiple reducers.
It ensures sorting orders of values present in multiple reducers
For example, Cluster By clause mentioned on the Id column name of the table employees_guru table. The output when executing this query will give results to multiple reducers at the back end. But as front end it is an alternative clause for both Sort By and Distribute By.
This is actually back end process when we perform a query with sort by, group by, and cluster by in terms of Map reduce framework. So if we want to store results into multiple reducers, we go with Cluster By.
From the above screen shot we are getting the following observations:
It is the query that performs CLUSTER BY clause on Id field value. Here it’s going to get a sort on Id values.
It displays the Id and Names present in the guru_employees sort ordered by
Query:SELECT Id, Name from employees_guru CLUSTER BY Id; Distribute By:
Distribute BY clause used on tables present in Hive. Hive uses the columns in Distribute by to distribute the rows among reducers. All Distribute BY columns will go to the same reducer.
It ensures each of N reducers gets non-overlapping ranges of column
It doesn’t sort the output of each reducer
From the above screenshot, we can observe the following
DISTRIBUTE BY Clause performing on Id of “empoloyees_guru” table
Output showing Id, Name. At back end, it will go to the same reducer
Query:SELECT Id, Name from employees_guru DISTRIBUTE BY Id;
You're reading Hive Queries: Order By, Group By, Distribute By, Cluster By Examples
StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentFirstName varchar(100), StudentMarks int ); Query OK, 1 row affected (0.16 sec) Query OK, 1 row affected (0.15 sec) Query OK, 1 row affected (0.19 sec) Query OK, 1 row affected (0.19 sec) Query OK, 1 row affected (0.18 sec) Query OK, 1 row affected (0.13 sec) | StudentId | StudentFirstName | StudentMarks | | 1 | John | 45 | | 2 | NULL | 65 | | 3 | Chris | 78 | | 4 | NULL | 89 | | 5 | Robert | 99 | | 6 | NULL | 34 | | 7 | Mike | 43 | | StudentId | StudentFirstName | StudentMarks | | 5 | Robert | 99 | | 7 | Mike | 43 | | 1 | John | 45 | | 3 | Chris | 78 | | 2 | NULL | 65 | | 4 | NULL | 89 | | 6 | NULL | 34 | 7 rows in set (0.00 sec)
Sleek by 50 Headphones Finished, G-Unit and Sleek Part Ways, World Weeps
Did you know that rapper 50 Cent had his own line of headphones? We did, we got a look at the units way back at the beginning of this year at CES 2011 – $400 headphones with some lovely features, the unit called a “Wireless Hybrid,” able to work with or without a cord – the cord in place incase you run out of rechargeable power. All that’s over now! It seems that 50 Cent and his G-Unit have decided that they don’t agree with the path that Sleek by 50 was going down, thusly Sleek and the rap label have parted ways. Let’s have a moment of silence for what was certainly going to be the most important collaboration of our time.
Sleek Audio LLC (“Sleek”) and G-Unit Brands, Inc. (“G-Unit”) have officially canceled their plans to develop products under the “Sleek by 50” brand. In addition to the headphones, they’ve of course decided to cut ties between G-Unit and TV Goods, Inc, which would have been where video production took place for commercials and whatnot. Sleek is currently “re-evaluating” their over-the-ear headphones for a later date, while 50 and crew are more than likely thinking about how terrible it is not to have their own headphone line.
Meanwhile, the rumors continue to surround the rapper and his former good pal Dr Dre, the man credited on many fronts with bringing the currency-themed artist to the forefront some 10 years ago with his buddy Eminem. These rumors of hate between the tag team of Eminem and Dre vs 50 culminate at the music video “I Need a Doctor” which features a montage of Dre’s portages but fails to include 50, one of his biggest. What could it mean? Folks in the rap community are adamant that it means that Dre is kind of sort of peeved that his good buddy would attempt to take away any of his Beats by Dre market away with a 50 Cent headphones line.
Either way, no more 50 Cent headphones. Saddest day ever. Take a peek at the press release below and the “I Need a Doctor” video above for some bonus HP TouchPad and Pre3 action. You know you want it!
Sleek Audio and G-Unit Brands, Inc, 50 Cent’s Licensing Company, Cancel Plans to Develop Products Under the “Sleek by 50” Brand
Palmetto, Fl. XX, 2011 – Sleek Audio today announced the termination of the Brand License Agreement between Sleek Audio LLC (“Sleek”) and G-Unit Brands, Inc. (“G-Unit”), 50 Cent’s licensing company. In addition, the Brand License Agreement, including video production, between TV Goods, Inc, Sleek and G-Unit has also been terminated.
“We will be re-evaluating our Wireless Hybrid over-the-ear headphones at a later date. Currently we are working to bring our new, U.S.-made in-ear products to the market,” said Mark Krywko, CEO of Sleek Audio.
Sleek Audio is in production of the highly anticipated, U.S.-made SA6-R Wireless Hybrid earphone and award-winning SA7 earphone, which earned the Best of Innovations title in the headphone category at CES 2011. Sleek is also producing its acclaimed PRO Series comprised of hand-made, Wireless Hybrid custom earphones including the CT6 and all-new CT7.
So you want to be a wedding photographer. Question is, what camera gear do you need?
To answer that, let’s take a look inside the camera bags of hundreds of top wedding photographers from around the world.
Though each of their kits is unique, learning about what equipment they use and why is a great way to start (or upgrade) your own wedding photography kit.
If you’re completely new to wedding photography and want to make it your profession, here’s something you should know: you can do a lot with very little.
Besides your camera, the most important tool to have in your bag is creativity (well, maybe a spare battery!). Remember that for the client, the most important thing is that you capture the emotions and unique moments of the day.
That said, a better quality camera will help you nail more usable shots – especially if you find yourself shooting in low-light situations or trying to capture fast-paced action.
That’s why most of the wedding photographers featured here opt for high-quality DSLRs or full-frame mirrorless cameras.
You’ll also notice that most have more than one body in their wedding photography kit. This is for several reasons: if something goes wrong with one camera body, you should always have a backup. This wedding is not going to happen again!
And secondly, you can have a different lens attached to each, allowing you to quickly switch between focal lengths.
Some wedding photographers prefer to kit out their bag with prime lenses, opting to embrace the creative limitations of a fixed focal length. Others are content with a bag full of zooms.
One of the big deciding factors in gear is the style of wedding photography you want to shoot. On one end of the spectrum, you have perfectly posed wedding photography.
This type of wedding photography favours engineered “moments”, posed wedding portraits, and magazine-worthy photos of settings and details.
On the other extreme is pure documentary: a wedding day captured with all its raw emotion, awkward family interactions and drunk dancefloor shenanigans kept intact and unadulterated.
Realistically, the majority of wedding photographers shoot some combination of the two. Their preference for one or the other will, however, have some influence over the gear they choose.
Documentary wedding photographers, for example, will go for more discreet equipment: lenses with longer focal lengths that allow them to keep a distance from the action, natural light over obtrusive flashes, and silent shutters that don’t break the tension of an emotion-filled moment.
Beyond cameras and lenses, you’ll find that our featured wedding photographers’ kits include a whole range of intriguing bits and pieces.
Drones are becoming more popular as an additional wedding photography tool. Speedlights, gels and modifiers for after sundown. Ergonomic camera straps or harnesses for long days of shooting.
Comfortable shoes. Earplugs. Snacks.
(We’ll say it again: you can learn a lot from other people’s mistakes!)
If you love weddings and find fulfilment in being able to immortalise people’s most emotion-filled and precious moments, this is definitely a genre and career worth pursuing.
Finding the right gear is just the beginning. But it makes all the difference to becoming the best wedding photographer you can be.
Get inspired by checking out the wedding photographer features above.
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Excel functions, formula, charts, formatting creating excel dashboard & othersIntroduction to Automation in Excel
Automation in Excel generally involves coding in VBA (Visual Basic for Applications), a variation of Visual Basic Language to integrate with Microsoft Office applications. It is an Excel-based programming language that helps users automate tasks by writing or recording macros. A macro is a code that runs in an Excel environment and is used to automate repetitive tasks, such as when you must repeat a set of actions multiple times. Excel can record these actions and generate a macro containing code to repeat those steps. After recording the macro, the set of actions can be repeated by running the recorded macro. The macro produces VBA code users can view via VBE in a module.
Users employ Automation Add-Ins like XLTools and AutoMacro to automate their routine Excel tasks without relying on macros.Examples of Excel Automation
Let us see below how a recorded macro can automate a daily report.
You can download this Automation Excel Template here – Automation Excel TemplateExample #1 – Automation via Macro Recording
We have a dataset of some numbers and wish to have row-wise summary statistics (like sum, average, minimum, and maximum) for these. Also, we wish to apply some formatting styles to the dataset. We record these steps in a macro so that whenever we have a new dataset that requires the same operations, we can run this recorded macro to accomplish the task.
Let’s see what the dataset looks like:
Now to do the required operations and record it in a macro, we will follow the below process:
On doing this, a pop-up window opens as follows.
Now we can perform the required operations on the dataset as follows.
After using the formula, the result is shown below.
Applying the Average Formula in cell H2, the result is shown below.
Applying MIN Formula in cell I2, the result is shown below.
Applying the MAX formula in cell J2, the result is shown below.
Now drag these to get these statistics for all the rows.
Now when all these operations are performed, we stop recording the macro as below.Example #2 – Using the Recorded Macros
Now let’s say we have another similar dataset like this in ‘Example #2’ of the Excel file, which requires the same operations and formatting. So to do this, we just run the above-recorded macro, and our task will be accomplished.
So we can see in the above screenshot that on running the recorded macro named ‘Marks_macro1’, we have automated and hence replicated the operations done on Sheet1 in Example1 to Sheet2. This is automation via recording a macro.
This kind of automation is use for simple repetitive operations such as daily report formatting, database communication, file merging, document creation, data manipulation, and more.How Macros are Saved as VBA Code Procedures in VBE
Access the Visual Basic Editor by pressing Alt+F11 to open the Visual Basic Editor window.
On doing this, a window opens. Under the ‘Project-VBAProject’ pane, we will store the macro in one module.
With VBA Macro Recorder, we do not need to code the macro; instead, we just record it.
Users can store the macros in a personal workbook, a hidden workbook that opens in the background whenever Excel is started. Saving the macros in a Personal workbook makes the macro always available since the Personal Workbook is not system or file specified.
Excel always produces a sub-procedure (not a function procedure) when recording macros. So, recorded codes are only useful for simple macros. More complex macros can be generated by writing VBA codes by enabling the “Developer’ menu in Excel.
Recording macros to automate tasks can have some limitations. It may not always be possible to record macros that work exactly as we wish. The macro code often requires some manual updates, so in that case, AutoMacro can be used, which is an Add-In that directly installs into VBE. It requires very little knowledge of VBA coding.Things to Remember about Excel Automation
Some tools used for Excel automation without coding knowledge are Power Query, VBA Macro Recorder, and Automation Add-Ins like Auto Macro and XLTools. XLTools is an automation Add-In that can integrate Excel with other applications and tools like SQL and Python. It can use to write commands in simple Excel tables.
Users can add macros to the Excel function menu with a button available, similar to Excel’s built-in functions.
Recording a macro helps us perform simple repetitive tasks and also when we are writing complex macro codes by editing the recorded codes.Recommended Articles
This is a guide to Excel Automation. Here we discuss how to automate tasks by writing or recording macros, practical examples, and a downloadable Excel template. You can also go through our other suggested articles –
Alleged Sorority Hazing Investigated by University, Police Sigma Delta Tau suspended during probe
Dean of Students Kenneth Elmore is weighing the fate of the Sigma Delta Tau sorority after it was temporarily suspended earlier this month for alleged alcohol-related hazing.
Elmore says the University is investigating both the group and roughly 20 individual students—SDT sisters and members of an undisclosed fraternity—involved in the alleged hazing. The fraternity is not recognized by BU, unlike SDT before its suspension.
“Given the facts we had, I asked that SDT be suspended pending our ability to investigate this,” says Elmore (SED’87). He hopes to wrap up the inquiry by the end of next week and says most students involved have been cooperative.
If the allegations are judged true, the sorority could face permanent suspension, while individuals found to have violated BU’s conduct policies “could warrant suspensions or worse,” Elmore notes. “Any organization that has members who are going to be complicit with hazing or haze other students should expect that they are not going to be associated with BU.”
This is the first reported allegation of hazing at BU in more than a decade, according to the dean. “I’m particularly disappointed,” he says, because of the timing: just this past January, in the wake of incidents elsewhere, Elmore met with student organization leaders, including those from fraternities and sororities, to talk about hazing. He says he discussed with the leaders that Massachusetts outlaws hazing and that “there’s just no place at all for hazing in these organizations and in this community.”
The March 3 incident, first reported by the Daily Free Press, began when students summoned an ambulance for an intoxicated female student on Ashford Street around 9 p.m., according to BUPD Lieutenant Peter DiDomenica. About an hour later, he says, BUPD officers stopped three men helping a second woman who also appeared intoxicated. “It caused concern for her medical condition,” and the officers arranged for her to go to the hospital as well, DiDomenica says.
“My understanding was they were treated and released,” says Elmore.
Further investigation revealed that the drinking was part of an alleged hazing at an off-campus private residence. Aside from the University probe, Boston police and the BUPD are investigating possible violations of the state’s anti-hazing law, according to DiDomenica. Hazing is a misdemeanor punishable by up to a $3,000 fine and a year in jail.
Marisa Feehan (CAS’12) and Juliette Miller (CAS’12), respectively the president and vice president of campus affairs for the Panhellenic Council, which governs the University’s recognized sororities, issued a public statement deploring “any behavior that threatens the well-being of any member of Greek Life,” and saying, “we will not accept the occurrence of such incidents.”
The council lifted its SDT recognition, the statement says, but also urges the University community to “support each other and the sisters of Sigma Delta Tau.”
The alleged hazing drew local media attention to BU at a time when two former members of the hockey team are facing sexual assault charges. President Robert A. Brown appointed a task force earlier this month to report by this summer on the culture of the hockey team.
Against that backdrop, Elmore says, “I want to remind folks the overwhelming majority of our students are doing the right thing. Real community holds its own accountable, and we’ve been consistent in terms of doing that. In social situations, we’ve got to be ‘present.’ We’ve always got to be folks who look after themselves. This community still moves on.”
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