1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
|
## ----echo = FALSE-------------------------------------------------------------
library(DBI)
knitr::opts_chunk$set(collapse = TRUE, comment = "#>")
## -----------------------------------------------------------------------------
#' Driver for Kazam database.
#'
#' @keywords internal
#' @export
#' @import DBI
#' @import methods
setClass("KazamDriver", contains = "DBIDriver")
## -----------------------------------------------------------------------------
#' @export
#' @rdname Kazam-class
setMethod("dbUnloadDriver", "KazamDriver", function(drv, ...) {
TRUE
})
## -----------------------------------------------------------------------------
setMethod("show", "KazamDriver", function(object) {
cat("<KazamDriver>\n")
})
## -----------------------------------------------------------------------------
#' @export
Kazam <- function() {
new("KazamDriver")
}
Kazam()
## -----------------------------------------------------------------------------
#' Kazam connection class.
#'
#' @export
#' @keywords internal
setClass("KazamConnection",
contains = "DBIConnection",
slots = list(
host = "character",
username = "character",
# and so on
ptr = "externalptr"
)
)
## -----------------------------------------------------------------------------
#' @param drv An object created by \code{Kazam()}
#' @rdname Kazam
#' @export
#' @examples
#' \dontrun{
#' db <- dbConnect(RKazam::Kazam())
#' dbWriteTable(db, "mtcars", mtcars)
#' dbGetQuery(db, "SELECT * FROM mtcars WHERE cyl == 4")
#' }
setMethod("dbConnect", "KazamDriver", function(drv, ...) {
# ...
new("KazamConnection", host = host, ...)
})
## -----------------------------------------------------------------------------
#' Kazam results class.
#'
#' @keywords internal
#' @export
setClass("KazamResult",
contains = "DBIResult",
slots = list(ptr = "externalptr")
)
## -----------------------------------------------------------------------------
#' Send a query to Kazam.
#'
#' @export
#' @examples
#' # This is another good place to put examples
setMethod("dbSendQuery", "KazamConnection", function(conn, statement, ...) {
# some code
new("KazamResult", ...)
})
## -----------------------------------------------------------------------------
#' @export
setMethod("dbClearResult", "KazamResult", function(res, ...) {
# free resources
TRUE
})
## -----------------------------------------------------------------------------
#' Retrieve records from Kazam query
#' @export
setMethod("dbFetch", "KazamResult", function(res, n = -1, ...) {
...
})
# (optionally)
#' Find the database data type associated with an R object
#' @export
setMethod("dbDataType", "KazamConnection", function(dbObj, obj, ...) {
...
})
## -----------------------------------------------------------------------------
#' @export
setMethod("dbHasCompleted", "KazamResult", function(res, ...) {})
|
