RequeteODBCwhere-class: Class "RequeteODBCwhere"

Description

SQL Query with WHERE and ORDER BY clauses.

Arguments

Objects from the Class

Objects can be created by calls of the form new("RequeteODBCwhere", where=character(),and=vector(),order_by=character()).

select:: Object of class "character" The "SELECT" part of the query
where:: Object of class "character" The "WHERE" part of the query
and:: Object of class "vector" The "AND" part of the query
order_by:: Object of class "character" The "ORDER BY" part of the query
sql:: Object of class "character" The query built by aggregating "select","where","and", and "order_by" slots
query:: Object of class "data.frame" The result of the query
open:: Object of class "logical" Should the connection remain open, choosing this ensures more rapid multiple queries
baseODBC:: Object of class "vector" The name, user and password of the database
silent:: Object of class "logical" TRUE if the query must be executed silently, FALSE else
etat:: Object of class "character" The state of the query (Connecting, successful,...)
connection:: Object of class "ANY" The database connection

Extends

Class "'>RequeteODBC", directly. Class "'>ConnectionODBC", by class "RequeteODBC", distance 2.

Methods

connect: signature(object = "RequeteODBCwhere"): Connect to the database

Examples

Run this code

# NOT RUN {
showClass("RequeteODBCwhere")
# }
# NOT RUN {
 test<-0
 object=new("RequeteODBCwhere")
 object@baseODBC=c("myodbcconnection","myusername","mypassword")
 object@select= "select * from mytable limit 100"
 # assuming mycol, mycol1 and mycol2 are numeric
 object@where=paste(" where mycol>",test,sep="")
 object@and=paste(" and mycol2>",test," and mycol3<",test,sep="")
 object@order_by=" order by mycol1" 
 object<-connect(object)
 ## now object@sql contains the syntax of the query. 
 ## By changing the test variable, one can see how the
 ## function might be usefull
 ##  object@query contains the resulting data.frame
 
# }