Profile cover photo
Profile photo
Li David
9 followers
9 followers
About
Li's posts

Post has attachment
A Middleware for Data Reporting
Traditionally,
there are three ways to prepare data source for reporting: 1. Retrieve data by
directly connecting the reporting tool to the database and submit SQL
statements to the database in which data source is prepared; 2. Partial data preparation
is m...

Post has attachment
esProc Program: Operations of Table Sequences and Record Sequences(II)
2. Loop functions Loop functions can compute each record of a
table sequence/record sequence, express complex loop statements with simple
function. For instance, select is
used to make query, sort to sort, id to merge repeated records, pselect to fetch sequ...

Post has attachment
esProc Helps Process Structured Text in Java – Grouping and Summarizing
Following problems will arise if you
perform conditional filtering on text files in Java alone:  1. The text file is not a database, so it
cannot be accessed by SQL. The code needs to be modified if the expression of
grouping and summarizing is changed. Bes...

Post has attachment
esProc Helps Process Structured Text in Java–Conditional Filtering
Following problems will arise if you
perform conditional filtering on text files in Java alone:  1. The text file is not a database,so it
cannot be accessed by SQL. The code needs to be modified if filtering
conditions are changed. Besides, if you want a fl...

Post has attachment
esProc Program: Operations of Table Sequences and Record Sequences (I)
The esProc table sequence is a structured
two-dimensional table, having concepts of field, record, primary key and
reference. These concepts originate from the data table of relational database.
A table sequence is also an explicit set of genericity and ord...

Post has attachment
esProc Helps Process Heterogeneous Data Sources in Java - JSON
Java’s JSON open source package can only
parse JSON data and hasn't the computational function. It is troublesome for
programmers to develop a general program for performing computations, such as
grouping, sorting, filtering and joining, by themselves. For ...

Post has attachment
esProc Helps Process Heterogeneous Data Sources in Java – Excel
Generally, Java programmers use poi or other open source packages to
read and compute Excel data. These open source packages support low-level
programming, which increases the overall learning cost and complicates the
operation. But with the help of esProc,...

Post has attachment
esProc Helps Process Structured Text in Java–Conditional Filtering
Following problems will arise if you
perform conditional filtering on text files in Java alone:  1. The text file is not a database,soit
cannot be accessed by SQL. The code needs to be modified if filtering
conditions are changed. Besides, if you want a fle...

Post has attachment
esProc Helps Process Heterogeneous Data Sources in Java - HDFS
It is not difficult for Java to access HDFS
through API provided by Hadoop. But to realize computations, like grouping, filtering
and sorting, on files in HDFS in Java is troublesome. esProc is a good helper
in Java’s dealing with these computations. It can...

Post has attachment
esProc Helps Process Heterogeneous Data Sources in Java –Cross-Database Relating
JoinRowSet and FilteredRowSet provided by RowSet – Java's class
library for data computing – can perform cross-database related computing, but
they have a lot of weaknesses. First, JoinRowSet only supports inner join, it doesn't support outer join. Second, ...
Wait while more posts are being loaded