data type
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Library: Database access (OMDB)
Import : omdb.xmd |
The db.statement data type is used to receive the compiled SQL statement from db.compile-statement. Through this data type, the same SQL statement may be executed multiple times without the need to compile the statement at every execution. For some programs, this reduction in processing overhead can be significant.
To create a db.statement, use the db.compile-statement function. The resulting data type is a link to the compiled SQL statement. The statement can then be executed either by calling the db.execute function or by calling the db.streaming-execute function. All placeholder values must be specified at this time. If the statement is a query, the query results are retrieved through a db.field shelf. When you have finished using the statement, you can use db.discard to release the resources used by the db.statement data type.
Please refer to Opaque Data Types for a general description of opaque data types and how they are used.
The functions
db.compile-statement - compile a SQL statement.
db.discard - discard a compiled SQL statement.
db.execute - execute a compiled SQL statement, passing in parameters up front.
db.streaming-execute - execute a compiled SQL statement, streaming in parameters dynamically.