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
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
#' Backend: MySQL/MariaDB
#'
#' @description
#' See `vignette("translation-function")` and `vignette("translation-verb")` for
#' details of overall translation technology. Key differences for this backend
#' are:
#'
#' * `paste()` uses `CONCAT_WS()`
#' * String translations for `str_detect()`, `str_locate()`, and
#' `str_replace_all()`
#' * Clear error message for unsupported full joins
#'
#' Use `simulate_mysql()` with `lazy_frame()` to see simulated SQL without
#' converting to live access database.
#'
#' @name backend-mysql
#' @aliases NULL
#' @examples
#' library(dplyr, warn.conflicts = FALSE)
#'
#' lf <- lazy_frame(a = TRUE, b = 1, c = 2, d = "z", con = simulate_mysql())
#' lf %>% transmute(x = paste0(d, " times"))
NULL
#' @export
#' @rdname backend-mysql
simulate_mysql <- function() simulate_dbi("MariaDBConnection")
#' @export
dbplyr_edition.MariaDBConnection <- function(con) {
2L
}
#' @export
dbplyr_edition.MySQL <- dbplyr_edition.MariaDBConnection
#' @export
dbplyr_edition.MySQLConnection <- dbplyr_edition.MariaDBConnection
#' @export
db_connection_describe.MariaDBConnection <- function(con) {
info <- dbGetInfo(con)
paste0(
"mysql ", info$serverVersion, " [",
info$username, "@", info$host, ":", info$port, "/", info$dbname,
"]"
)
}
#' @export
db_connection_describe.MySQL <- db_connection_describe.MariaDBConnection
#' @export
db_connection_describe.MySQLConnection <- db_connection_describe.MariaDBConnection
#' @export
sql_translation.MariaDBConnection <- function(con) {
sql_variant(
sql_translator(.parent = base_scalar,
as.logical = function(x) {
sql_expr(IF(!!x, TRUE, FALSE))
},
as.character = sql_cast("CHAR"),
# string functions ------------------------------------------------
paste = sql_paste(" "),
paste0 = sql_paste(""),
# stringr
str_c = sql_paste(""),
# https://dev.mysql.com/doc/refman/8.0/en/regexp.html
# NB: case insensitive by default; could use REGEXP_LIKE for MySQL,
# but available in MariaDB. A few more details at:
# https://www.oreilly.com/library/view/mysql-cookbook/0596001452/ch04s11.html
str_detect = sql_infix("REGEXP"),
str_like = function(string, pattern, ignore_case = TRUE) {
if (isTRUE(ignore_case)) {
sql_expr(!!string %LIKE% !!pattern)
} else {
sql_expr(!!string %LIKE BINARY% !!pattern)
}
},
str_locate = function(string, pattern) {
sql_expr(REGEXP_INSTR(!!string, !!pattern))
},
str_replace_all = function(string, pattern, replacement){
sql_expr(regexp_replace(!!string, !!pattern, !!replacement))
}
),
sql_translator(.parent = base_agg,
sd = sql_aggregate("STDDEV_SAMP", "sd"),
var = sql_aggregate("VAR_SAMP", "var"),
str_flatten = function(x, collapse = "") {
sql_expr(group_concat(!!x %separator% !!collapse))
}
),
sql_translator(.parent = base_win,
sd = win_aggregate("STDDEV_SAMP"),
var = win_aggregate("VAR_SAMP"),
# GROUP_CONCAT not currently available as window function
# https://mariadb.com/kb/en/library/aggregate-functions-as-window-functions/
str_flatten = win_absent("str_flatten")
)
)
}
#' @export
sql_translation.MySQL <- sql_translation.MariaDBConnection
#' @export
sql_translation.MySQLConnection <- sql_translation.MariaDBConnection
#' @export
sql_table_analyze.MariaDBConnection <- function(con, table, ...) {
build_sql("ANALYZE TABLE ", as.sql(table, con = con), con = con)
}
#' @export
sql_table_analyze.MySQL <- sql_table_analyze.MariaDBConnection
#' @export
sql_table_analyze.MySQLConnection <- sql_table_analyze.MariaDBConnection
#' @export
sql_query_join.MariaDBConnection <- function(con, x, y, vars, type = "inner", by = NULL, ...) {
if (identical(type, "full")) {
cli_abort("MySQL does not support full joins")
}
NextMethod()
}
#' @export
sql_query_join.MySQL <- sql_query_join.MariaDBConnection
#' @export
sql_query_join.MySQLConnection <- sql_query_join.MariaDBConnection
#' @export
sql_expr_matches.MariaDBConnection <- function(con, x, y) {
# https://dev.mysql.com/doc/refman/5.7/en/comparison-operators.html#operator_equal-to
build_sql(x, " <=> ", y, con = con)
}
#' @export
sql_expr_matches.MySQL <- sql_expr_matches.MariaDBConnection
#' @export
sql_expr_matches.MySQLConnection <- sql_expr_matches.MariaDBConnection
#' @export
sql_values_subquery.MariaDBConnection <- function(con, df, types, lvl = 0, ...) {
sql_values_subquery_default(con, df, types = types, lvl = lvl, row = TRUE)
}
#' @export
sql_values_subquery.MySQL <- sql_values_subquery.MariaDBConnection
#' @export
sql_values_subquery.MySQLConnection <- sql_values_subquery.MariaDBConnection
#' @export
sql_random.MariaDBConnection <- function(con) {
sql_expr(RAND())
}
#' @export
sql_random.MySQLConnection <- sql_random.MariaDBConnection
#' @export
sql_random.MySQL <- sql_random.MariaDBConnection
#' @export
sql_query_update_from.MariaDBConnection <- function(con, x_name, y, by,
update_values, ...,
returning_cols = NULL) {
# https://stackoverflow.com/a/19346375/946850
parts <- rows_prep(con, x_name, y, by, lvl = 0)
update_cols <- sql_table_prefix(con, names(update_values), x_name)
clauses <- list(
sql_clause_update(x_name),
sql_clause("INNER JOIN", parts$from),
sql_clause_on(parts$where, lvl = 1),
sql_clause_set(update_cols, update_values),
sql_returning_cols(con, returning_cols, x_name)
)
sql_format_clauses(clauses, lvl = 0, con)
}
#' @export
sql_query_update_from.MySQLConnection <- sql_query_update_from.MariaDBConnection
#' @export
sql_query_update_from.MySQL <- sql_query_update_from.MariaDBConnection
#' @export
supports_window_clause.MariaDBConnection <- function(con) {
TRUE
}
#' @export
supports_window_clause.MySQLConnection <- supports_window_clause.MariaDBConnection
#' @export
supports_window_clause.MySQL <- supports_window_clause.MariaDBConnection
globalVariables(c("%separator%", "group_concat", "IF", "REGEXP_INSTR", "RAND", "%LIKE BINARY%"))
|
