We often need to sort or rank data during data statistics and analysis. The operations include problems like sort sales records according to the dates and rank the results of salespersons for assessing their performance.
1. Sort and rank members in a sequence
In esProc, functions, such as psort, sort, ranki rank, and e...
2014-12-30 489 0
Java programs can call esProc via JDBC. It is necessary for programmers to know how to deploy the esProc JDBC and familiarize themselves with the detailed configuration information.
1． Basic steps
The following instructions need to be followed to deploy the esProc JDBC:
1) Load necessary jars
Load the jars needed by es...
2014-12-29 761 0
In esProc, strings are not merely a data type; they can also be used as macros or string constants to construct expressions, or employed by eval() function to generate expressions dynamically as needed.
Macros in esProc refer to strings for composing expressions, only that these strings are usually generated d...
2014-12-26 454 0
In esProc Getting Started: Types of Cells, we learned that cells in esProc have many types, including constant cell, computational cell, executable cell and comment cell, and etc. The code blocks into which code is written in esProc also have the similar types: computational block, assignment block, executable block an...
2014-12-25 438 0
The command line refers to using commands in the form of strings in DOS-like environment to execute programs. All operating systems support the command lines, like the Linux console and the Windows command line window.
The file, esprocx.exe, is needed when the command line is used to execute an esProc cellset file. The...
2014-12-24 630 0
It is difficult to perform inter-row computation of continuous summary value in Excel. Usually we have to enter all formulas by hand, which is a taxing job and easy to get wrong. This is because Excel can merely copy formulas mechanically based on relative position and cannot process the formulas of inter-row computati...
2014-12-24 367 0
Besides data tables, store procedures are also very important for a database. esProc can call database stored procedures conveniently. This article will illustrate in detail how to call various stored procedures with db.proc() function in esProc.
1. Call stored procedures without return values
2014-12-23 468 0
Sometimes we need to fetch certain data from multiple files of a multi-level directory during text processing. The operation is too complicated to be well performed at the command line. Though it can be realized in high-level languages, the code is difficult to write; and the involvement of big files will increase the ...
2014-12-22 482 0
During text processing, sometimes we need to replace multiple strings in the source file according to a criteria file. The command line can be used to replace a single string, but it cannot realize the batch string replacement. High-level languages can only handle this task through complicated multilayer loops. If the ...
2014-12-19 419 0
3. No result or multiple results
It is allowed to return no result during calling a cellset file. Take the following cellset file – outputData1.dfx – as an example:
$(demo) select * from CITIES
2014-12-18 493 0
esProc can be embedded in a Java application. Invoking an esProc cellset program is like accessing a database via JDBC. During the invocation the cellset program is packaged as a stored procedure, so it is called in the same way as that the latter is called.
1. Basic usage
esProc JDBC resembles a database JDBC dr...
2014-12-17 839 0
Excel has difficulty in performing the inter-row computation of summary value, because it lacks a smart adjustment mechanism and can only copy the formulas based on their relative positions. Therefore it requires entering the formulas by hand, which is not only a laborious job but easy to get wrong. But in esCalc, you ...
2014-12-17 399 0
The join statements of the database can be used conveniently to perform the operation of alignment join. But sometimes the data is stored in the text files, and to compute it in Java alone we need to write a large number of loop statements. This makes thecode cumbersome. Using esProc to help with programming in Java ca...
2014-12-16 383 0
Sometimes during text processing you need to find out words containing certain characters. The logic of this computation is simple, but the code is difficult to write using the regular expression because the order of the characters is flexible. Moreover, the method is inefficient. You may do better to write the program...
2014-12-15 367 0
It is difficult for MongoDB to realize the operation of cross summarizing. It is also quite complicated to realize it using high-level languages, like Java, after the desired data is retrieved out. In this case, you can consider using esProc to help MongoDB realize the operation. The following example will teach you ho...
2014-12-12 439 0