I have 3 tables on mysqlworkbench, 1 table need to combine with 2 data ch(17million row) and cl(9million row) suppose to be one table, other table name alldoc.(121k)
Basically i need to combine ch and cl as one table, and compare with alldoc data. Technically they are suppose to be same but people made mistake that why i need to compare. 100 column
enter image description here
enter image description here
I plan to write query till i hit to 100 because i have 100 columns in all data. Just rows sizes are different.
Thank you from advance. I know complicated but i really need to compare these two data writing query
Related
I have a large set of data, however below shows only 4 entries. I want to isolate the rows that have the same entries. For instance, on table one you can see that the first two rows have the same value in the columns number, ID, Brand, and Partner. I want to only get the rows with these same entries, so my final result will be Data Table 2.
Data Table
Data Table 2
This is the quickest way I can think of
https://drive.google.com/file/d/1Ufbl6J-gwCi5OpqaGHmC93aHuA6g-gSi/view?usp=sharing
Actually, I've just realised the 'RecordID' is redundant so you can leave that tool out, I think?
I have a dataset containing roughly 50 columns. I want to check the data inputs and show how many blanks/if any are in each column.
I originally started using calculated fields for columns and using sum(if isnull([column] then 1 else 0 end)). This works but doesn’t seem very efficient if I want to do it for multiple columns.
Tried doing a pivot table as well however I need the data in it’s original form for other analysis I would like to do.
Would appreciate any help.
Thanks
Fiona
I'm using Dataprep on GCP to wrangle a large file with a billion rows. I would like to limit the number of rows in the output of the flow, as I am prototyping a Machine Learning model.
Let's say I would like to keep one million rows out of the original billion. Is this possible to do this with Dataprep? I have reviewed the documentation of sampling, but that only applies to the input of the Transformer tool and not the outcome of the process.
You can do this, but it does take a bit of extra work in your Recipe--set up a formula in a new column using something like RANDBETWEEN to give you a random integer output between 1 and 1,000 (in this million-to-billion case). From there, you can filter rows based on whatever random integer between 1 and 1,000 as what you'll keep, and then your output will only have your randomized subset. Just have your last part of the recipe remove this temporary column.
So indeed there are 2 approaches to this.
As Courtney Grimes said, you can use one of the 2 functions that create random-number out of a range.
randbetween :
rand :
These methods can be used to slice an "even" portion of your data. As suggested, a randbetween(1,1000) , then pick 1<x<1000 to filter, because it's 1\1000 of data (million out of a billion).
Alternatively, if you just want to have million records in your output, but either
Don't want to rely on the knowledge of the size of the entire table
just want the first million rows, agnostic to how many rows there are -
You can just use 2 of these 3 row filtering methods: (top rows\ range)
P.S
By understanding the $sourcerownumber metadata parameter (can read in-product documentation), you can filter\keep a portion of the data (as per the first scenario) in 1 step (AKA without creating an additional column.
BTW, an easy way of "discovery" of how-to's in Trifacta would be to just type what you're looking for in the "search-transtormation" pane (accessed via ctrl-k). By searching "filter", you'll get most of the relevant options for your problem.
Cheers!
I have a table with 28 million rows that I want to update. It has around 60 columns and a ID column (primary key) with an index created on it. I created four new columns and I want to populate them with the data from four columns from other table which also has an ID column with an index created on it. Both tables have the same amount of rows and just the primary key and the index on the IDENTI column. The query has been running for 15 hours and since it is high priority work, we are starting to get nervous about it and we don't have so much time to experiment with queries. We have never update a table so big (7 GB), so we are not sure if this amount of time is normal.
This is the query:
UPDATE consolidated
SET IDEDUP2=uni.IDEDUP2
USE21=uni.USE21
USE22=uni.USE22
PESOXX2=uni.PESOXX2
FROM uni_group uni, consolidated con
WHERE con.IDENTI=uni.IDENTI
How can I make it faster? Is it possible? If not, is there a way to check how much longer it is going to take (without killing the process)?
Just as additional information, we have ran before much more complex queries for 3 million row tables (postgis) and It has taken it about 15 hours as well.
You should not repeat the target table in the FROM clause. Your statement creates a cartesian join of the consolidated table with itself, which is not what you want.
You should use the following:
UPDATE consolidated con
SET IDEDUP2=uni.IDEDUP2
USE21=uni.USE21
USE22=uni.USE22
PESOXX2=uni.PESOXX2
FROM uni_group uni
WHERE con.IDENTI = uni.IDENTI
I'm working in Pentaho 4.4.1-GA (Kettle / PDI). The database is Postgres.
I need to be able to insert multiple records into a fact table based on the fields that come from a single record. The single record contains fields:
productcode1, price1
productcode2, price2
productcode3, price3
...
productcode10,price10
So if there was a value for each of the 10 productcode / prices then I'd need to insert a total of 10 records into the fact table. If there were values for 4 of the combinations, then I'd need to insert 4 records into the fact table, etcetera. All field values for the fact records would be identical except for the PK (generated by sequence), product codes, and prices.
I figure that I need some type of looping construct which would let me check whether or not a value was present for each productx field, and if so, do an insert/update step on the fact table with the desired field values. I'm just not sure how to do this in Pentaho.
Any ideas? All suggestions are welcome :)
Thank You,
Rakesh
Could you give a sample input and output for your scenario??
From your example data I can infer that if there are 10 different product codes and only 4 product prices you want to have 4 records inserted into your table. Is that so?
Well for a start you can add a constant value of 1 to those records by filtering for NOT NULL and then use an Group BY Step to count the number of 1's. This would give you the count. BTW it would be helpful if you could provide more details on what columns you would be loading as there are ways to make a PDI transformation execute multiple times