Reference:2.Sequence and TSeq

Sequence is an ordered set consisting of some data, and the constitutive data of a sequence is called Member. Sequence is equivalent to the array in the high level language. The difference is that the member of sequence does not have to be of the same type. The sequence is the most common unit in esProc.

temp2

Some members enclosed in a [] forms a constant sequence. The sequence can be defined in an expression in a format similar to the constant sequence, and the cell can be used in an expression.

If no member exists in sequence, then you can use [] to define the empty sequence.

Image

The cell values of A1 and A3 can be viewed in the Data View section.

Image

esProc inherits the data table concept of relational database, and defines it as Table Sequence or TSeq for short. Consistent with the concept of rational database, in esProc, every Table Sequence also has its own Data Structure, which consists of several Fields. The member of table sequence is also called as Record. TSeq is a sequence whose members are all records.

TSeq can be retrieved from database or converted from the data of text file. When using the data of text file, you can separate the data of the same row with Tab.

Image

Sequence consisting of records from table sequence is called Record Sequence or RSeq for short. The members of record sequence are not definitely from a same table sequence. The record sequence whose members are from a same table sequence is called as Pure Record Sequence.

Advertisements

About datathinker

a technical consultant on Database performance optimization, Database storage expansion, Off-database computation. personal blog at: datakeywrod, website: raqsoft
This entry was posted in Reference and tagged , , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s