In the big data computing, besides the grouping and aggregate operations, sometimes you also need to retrieve a group of data each time to analyze. For example, analyze the sales by date, collect statistics on sales curve for each product, and the purchase habit of each client.
In esProc, you can use function cs.fetch(...
2014-08-11 13 0
With esProc, the big structured data can be handled easily, and the computation and analysis over big data can be accomplished smoothly. Because the big data table cannot be loaded into the memory all at once, the basic solution is cursor when handling the big data.
1. Basic principle of cursor
The esProc cursor is lik...
2014-08-08 11 0
In esProc computing, we may frequently use constants or store the data in the cell directly. In this article, let’s learn the usage of constants in the esProc.
1.Directly using constant in the expression
Constants can be directly used in the esProc expression:
When using the constant in the expression, the integer and...
2014-08-05 17 0
Both R language and esProc have the outstanding ability to perform the stepwise computations. However, in the particulars they differ from each other. A comparison between them will be done by the following example:
A company’s Sales department wants to select out the outstanding salespersons through statistics, that i...
2014-07-31 10 0
A sequence is an ordered set consisting of some data, which are called members of the sequence. A sequence is similar to an array in high-level language, but the data type of its members not have to be the same. The following will explain its basic computation through creation, access, operators and functions.
2014-07-29 28 0
esProc table sequence is a structured two-dimensional table, boasting concepts like field, record, primary key and reference. These concepts originate from data table of relational database. A table sequence is also an explicit set of genericity and orderliness, which can make computation of structured data more flexib...
2014-07-28 16 0
Sequence,table sequence and record sequence are commonest data types of esProc. This article tries to expound their respective characteristics as well as relations between them.
A sequence is an ordered generic set
A sequence consists of multiple data,which are members of the sequence. The members can be ...
2014-07-23 31 0
Since sets are commonly used in esProc, the latter provides comprehensive set operations.
1.Binary Operation on Sets
The most basic set in esProc is sequence. Let’s look at some basic binary operations between two sequences A and B.
Concatenate: Concatenate the two sequence straightforwardly, of which the member ...
2014-07-22 26 0
In Java, implementing via SQL is a well-developed practice for database computation. However, the structured data is not onlystored in the database, but also in the text, Excel, and XML files. Considering this, how to compute appropriately regarding the structured data from non-database files? This article raises 3 sol...
2014-07-18 30 0
Report developers always encounter some complex reports, which are few in number but need a lot of development time.Sometimes,they even become difficult problems. This article will dig for the root of such complexity, and the methods to resolve them. Hopefully this helps to improve report development efficiency.
2014-07-17 24 0
Fibonacci Sequence is also called “Rabbit Sequence”, because it can be described by a problem related to rabbits: After the second month of their life, a pair of rabbits can give birth to two little ones every month. If all the rabbits could live forever, then how many pairs of rabbits are there in the nth month?
2014-07-15 11 0
=tbl.delete([1,3,5]) // Delete Records 1, 3 and 5
=tbl.delete(15) // Delete Record 15
=tbl.delete(tbl.pselect@a(col1>50)) //Delete any record where col1>50 is true
splice(@myarray,1,3); #Subsequent three ele...
2014-07-14 12 0
=tbl.select(col1>5) //Get the set of row records where col1>5 is true, it supports the binary search for ordered table, and can return the first record or all the records
=tbl.pselect(col1>5) //Get the row number of record where col1>5 is true, it supports the binary...
2014-07-11 9 0
1.Foreign key referencing
The foreign key is a common concept for various relational databases. In a relational table, you can define one or multiple fields as the foreign key. The foreign key field values can be associated with the data in another table. For example, in the game scoring report, player scores are usual...
2014-07-10 18 0
Members in a set (sequence) of esProc are organized in order. Therefore, you can reference a member in a set with the serial number of the member. The more flexible use of serial number, the better esProc functions and the operation will be much simpler and more efficient.In fact, the serial number ...
2014-07-09 17 0