DEV Community

# esproc

Posts

👋 Sign in for the ability to sort posts by relevant, latest, or top.
Multi combination condition grouping and aggregation #eg93

Multi combination condition grouping and aggregation #eg93

5
Comments
1 min read
Split a Huge CSV File into Multiple Smaller CSV Files #eg69

Split a Huge CSV File into Multiple Smaller CSV Files #eg69

6
Comments 1
1 min read
Group & Summarize a CSV File #eg68

Group & Summarize a CSV File #eg68

6
Comments 1
1 min read
Getting positions of members according to primary key values #eg58

Getting positions of members according to primary key values #eg58

6
Comments
1 min read
Getting members according to primary key values #eg63

Getting members according to primary key values #eg63

7
Comments
1 min read
How to Access Databases using One SQL Statement #eg71

How to Access Databases using One SQL Statement #eg71

6
Comments
1 min read
Filter a CSV file and re-arrange it by category #eg60

Filter a CSV file and re-arrange it by category #eg60

6
Comments 1
1 min read
Getting positions of members based on a specified condition #eg46

Getting positions of members based on a specified condition #eg46

11
Comments
1 min read
Convert Each Whites-space-separated Text Block into a Row #eg62

Convert Each Whites-space-separated Text Block into a Row #eg62

7
Comments
1 min read
Perform Distinct on Ordered Numbers in a Text File #eg61

Perform Distinct on Ordered Numbers in a Text File #eg61

8
Comments
1 min read
Parse a csv file having a primary-sub tables structure #eg41

Parse a csv file having a primary-sub tables structure #eg41

6
Comments
2 min read
Convert CSV Data into Multilevel JSON #eg56

Convert CSV Data into Multilevel JSON #eg56

6
Comments
1 min read
Add a compute column to a csv file #eg40

Add a compute column to a csv file #eg40

6
Comments
1 min read
SQL, in each group modify the null value of a specified column as its neighboring value #eg43

SQL, in each group modify the null value of a specified column as its neighboring value #eg43

7
Comments
1 min read
Get the whole group where at least one member meets the specified condition #eg36

Get the whole group where at least one member meets the specified condition #eg36

6
Comments
2 min read
Parse a csv file where field values are enclosed by quotation marks and contain carriage return #eg35

Parse a csv file where field values are enclosed by quotation marks and contain carriage return #eg35

6
Comments
1 min read
Replace Duplicate Digits in Every 9-digit Number in a Text File with Non-duplicate Ones #eg52

Replace Duplicate Digits in Every 9-digit Number in a Text File with Non-duplicate Ones #eg52

7
Comments
1 min read
Reverse Rows in a Text File #eg51

Reverse Rows in a Text File #eg51

8
Comments 3
1 min read
The Difference between Each Value in a Certain Column and Its Previous One and Display Result

The Difference between Each Value in a Certain Column and Its Previous One and Display Result

6
Comments
2 min read
Java, perform COUNT on each group of a large csv file #eg33

Java, perform COUNT on each group of a large csv file #eg33

6
Comments
2 min read
SQL, extract unique values of JSON format field from each group #eg42

SQL, extract unique values of JSON format field from each group #eg42

6
Comments
2 min read
Multi-condition filtering #eg48

Multi-condition filtering #eg48

6
Comments
1 min read
Getting members based on a specified condition #47

Getting members based on a specified condition #47

6
Comments
1 min read
Read specified columns from a csv file #eg44

Read specified columns from a csv file #eg44

6
Comments
1 min read
Something could double the development efficiency of Java programmers

Something could double the development efficiency of Java programmers

7
Comments
6 min read
Java, fill each row having a null value in a csv file with values in the directly previous row #eg32

Java, fill each row having a null value in a csv file with values in the directly previous row #eg32

6
Comments
1 min read
To Index Data is To Sort Data

To Index Data is To Sort Data

8
Comments
5 min read
Clear duplicate lines and lines having missing values from a csv file #eg24

Clear duplicate lines and lines having missing values from a csv file #eg24

7
Comments 1
1 min read
SQL, Set different flags for different groups according to whether there are duplicate values #eg19

SQL, Set different flags for different groups according to whether there are duplicate values #eg19

8
Comments 1
1 min read
Add Missing Sequence Numbers to One Table according to The Other and Combine Two Tables #eg18

Add Missing Sequence Numbers to One Table according to The Other and Combine Two Tables #eg18

6
Comments 1
1 min read
Get the First Missing Item for the Sequence of Should-have-been Continuous Sequence Numbers #eg16

Get the First Missing Item for the Sequence of Should-have-been Continuous Sequence Numbers #eg16

6
Comments 1
2 min read
SQL, mark continuous rows with sequence numbers #eg30

SQL, mark continuous rows with sequence numbers #eg30

8
Comments
1 min read
SQL, get historical status of each ID #eg22

SQL, get historical status of each ID #eg22

8
Comments 1
1 min read
Compare two csv files #eg34

Compare two csv files #eg34

7
Comments 1
1 min read
SQL, output associated records having many-to-many relationship row by row #eg26

SQL, output associated records having many-to-many relationship row by row #eg26

8
Comments
1 min read
Retrieve multiple columns from a csv file to generate a new file #eg23

Retrieve multiple columns from a csv file to generate a new file #eg23

7
Comments 1
1 min read
SQL, compute cumulative sums according to the termination condition #eg29

SQL, compute cumulative sums according to the termination condition #eg29

7
Comments 1
1 min read
SQL, parse json data #eg28

SQL, parse json data #eg28

11
Comments
1 min read
SQL, concatenate multiple rows of strings and remove duplicates #eg27

SQL, concatenate multiple rows of strings and remove duplicates #eg27

6
Comments
1 min read
Calculate the Average Interval of Projects for Each User #eg17

Calculate the Average Interval of Projects for Each User #eg17

6
Comments 1
1 min read
Merge multiple files, remove duplicates and sort the result #eg25

Merge multiple files, remove duplicates and sort the result #eg25

6
Comments 1
1 min read
How to Display Dates Easily ? #eg9

How to Display Dates Easily ? #eg9

6
Comments 1
2 min read
Which Scenarios Does ClickHouse Applies to?

Which Scenarios Does ClickHouse Applies to?

6
Comments
5 min read
Is SQL a declarative language

Is SQL a declarative language

13
Comments 5
5 min read
How come there are tens of thousands of tables in a database

How come there are tens of thousands of tables in a database

7
Comments 1
5 min read
Translating Database Queries

Translating Database Queries

110
Comments 3
3 min read
What to do if the query calculation is moved out of database but is too slow using java

What to do if the query calculation is moved out of database but is too slow using java

7
Comments 1
6 min read
loading...