ISO IEC 19075-3 pdf – Information technology — Guidance for the use of database language SQL — Part 3: SQL embedded in programs using the Java programming language
1 Scope
This document describes the support for the use of SQL within programs written in Java.This document discusses the following features of the sQL language:
– The embedding of SQL expressions and statements in programs written in the Java programming language.
2Normative references
The following documents are referred to in the text in such a way that some or all of their content consti-tutes requirements of this document. For dated references, only the edition cited applies. For undatedreferences, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 9075-1, Information technology —Database languages —SQL—Part 1: Framework(sQL/Framework)
ISO/IEC 9075-10, Information technology —Database languages—SQL—Part 10: Object LanguageBindings (SQL/OLB)
Java Community Process. The Java T Language Specification [online]. Java SE 13 Edition. RedwoodShores,California,USA:Oracle,Availableathttps://docs.oracle.com/javase/specs/jls/-se13/jls13.pdf
Java Community Process.JDBCTM4.3 Specification [online].Edition 4.3.Redwood Shores, California,USA:Oracle, Available at https : / / download.oracle.com/otn-pub/jcp/- jdbc-4_3-mrel3-eval-spec/jdbc4.3-fr-spec.pdf
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 9075-1 apply.
IlSO and IEC maintain terminological databases for use in standardization at the following addresses:-IEC Electropedia: available at http : / / www .electropedia.org/
-ISo online browsing platform: available at http : / /www .iso.org/ obp
4 Use of sQL in programs written in Java
4.1Context of sQL programs written in Java
The requirements for the material discussed in this document shall be as specified in ISO/IEC 9075-1and lso/IEC 9075-10.
4.2Design goals
The following items represent the major design features of ISO/IEC 9075-1.ISO/IEC 9075-10, Java, andJDBC all specify requirements for the material discussed in this document.
– Provide a concise, legible mechanism for embedding SQL-statements in a program that otherwise
conforms to Java.
Syntactic and semantic check of SQL-statements prior to program execution.
sQL/OLB can use an implementation-defined mechanism at translate time to check embedded SQL-statements to make sure that they are syntactically and semantically correct.
Allow the syntax and semantics of SQL-statements to be location-independent.
The syntax and semantics of SQL-statements in an SQL/OLB program do not depend on the configu-ration under which SQL/OLB is running.This makes it possible to implement SQL/OLB programsthat run on the client, in the sQL-server, or in a middle tier.
Provide facilities that enable the programmer to move between the SQL/OLB and JDBCenvironmentsby sharing a single SQL-connection in both environments.
Provide for binary portability of translated and compiled Java SQL-client applications such that theycan be used transparently with multiple SQL-servers. ln addition, binary portability profiles allowfor customization and optimization of SQL-statements within an sQL/oLB application.
4.3Advantages of sQL/OLB over JDBC
JDBC. providesa complete,low-level SQLinterface from Java to SQL-implementations.SQL/OL.Bis designedto fill a complementary role by providing a higher-level programming interface to sQL-implementationsin such a manner as to free the programmerfrom the tedious and complex programminginterfaces foundin lower-level APls.
The followwing are some major differences between the two:
sQL/OLB source programs are smaller than equivalent JDBC programs since the translator canimplicitly handle many of the tedious programming chores that dynamic interfaces require.
sQL/OLB programs can type-check SQL code at translate time using an implementation-dependentmechanism. ]DBC, being a completely dynamic API, can not.
4.4Consistency with existing embedded sQL languages
Programming languages containing embedded SQL are called host languages. Java differs from the tradi-tional host languages(Ada, C, CoBOL, Fortran,MUMPS(M), Pascal,PL/1) in ways that significantly affectits embedding of SQL.
Java has automatic storage management (also known as “garbage collection”) that simplifies themanagement of storage for data retrieved from sQL-implementations.
All Java types representing composite data,and data of varying sizes, have a distinguished valuenull, which can be used to represent the SQL NULL value.This gives Java programs an alternativeto the indicator variables that are part of the interfaces to other host languages.
Java is designed to support programs that are automatically heterogeneously portable (also called“super portable” or simply “downloadable”).That, along with Java’s type system of classes andinterfaces,enables component software.In particular, an SQL/OLB translator, written in Java, cancall components that are specialized by sQL-implementations, in order to leverage the existingauthorization, schema checking, type checking, transactional, and recovery capabilities that are tra-ditionalofSQL-implementations,and to generate code optimized for particular SQL-implementations.Java is designed for binary portability in heterogeneous networks, which promises to enable binaryportability for applications that use sQL.
sQL/OLB extends the traditional concept of embedded host variables by allowing generalized hostexpressions.