Part VI in .NET

Insert data matrix barcodes in .NET Part VI

WIXON, DENNIS,

Software not available in .DEB or RPM formats can often be installed from installer scripts (.sh) or by compiling source code from tarball. A tarball is an archive of files created with a special utility (named tar) and usually compressed using another utility, gzip. Source code distributions are often packaged as gzipped tarballs. Compiling from source enables you to do things the old way if needed and to exercise granular control of unpackaged software. This functionality helps keep Linspire a flexible platform for running a variety of software.

xi yi = 0 (xi yi) + (vi vTyi)Dac (vi vTyi) =0

(7.6)

(continued)

SQL Server is based on the SQL standard, with some Microsoft-speci c extensions. SQL was invented by E. F. Codd while he was working at the IBM research labs in San Jose in 1971. SQL Server is entry-level (Level 1) compliant with the ANSI SQL 92 standard. (The complete speci cations for the ANSI SQL standard are found in ve documents that can be purchased from www.techstreet.com/ncits.html. I doubt if anyone who doesn t know exactly what to look for will nd these documents.) But it also includes many features de ned in later versions of the standard (SQL-1999, SQL-2003). While the ANSI SQL de nition is excellent for the common data-selection and data-de nition commands, it does not include commands for controlling SQL Server properties, or provide the level of logical control within batches required to develop a SQL Server speci c application. Therefore, the Microsoft SQL Server team has extended the ANSI de nition with several enhancements and new commands, and has left out a few commands because SQL Server implemented them differently. The result is Transact-SQL, or T-SQL the dialect of SQL understood by SQL Server. Missing from T-SQL are very few ANSI SQL commands, primarily because Microsoft implemented the functionality in other ways. T-SQL, by default, also handles nulls, quotes, and padding differently than the ANSI standard, although that behavior can be modi ed. Based on my own development experience, I can say that none of these differences affect the process of developing a database application using SQL Server. T-SQL adds signi cantly more to ANSI SQL than it lacks.

and then keeping the leading terms in the numerator up to order 3, we would get 2 2 2 T ({Dk ( )} , I ) |I =1 3D2 ( ) + D4 ( ) + 12D2 ( ) D4 ( ) = I

71 1

Unique functional materials might be created based on the cyclobutadienecobalt-containing polymers because of their chemical and thermal stability and of the peculiar square geometry of the cyclobutadiene ligands. Re ecting on the squarer geometry of the cyclobutadiene moieties, thermotropic liquid-crystalline polymers can be designed by the polycondensation of the regioisomerically pure organocobalt monomers.9 12 As shown in scheme 3, the Ni(0)-promoted dehalogenation polycondensation of both 1,2- and 1,3- regioisomerically pure bifunctional ( 5-cyclopentadienyl)( 4-cylobutadiene)cobalt complexes (6A and 6B) yields zigzag and rigid-rod -conjugated polyarylenes (7A and 7B), respectively.11 Both of these polymers exhibit thermotropic and, in some cases, lyotropic liquid-crystalline behavior. However the properties of these two series of the polymers are entirely di erent; the zigzag-type polymers (7A) exhibit thermotropic liquid crystals in a lower temperature range and higher solubility in organic solvents compared to the rigid-rod