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DBI method for creating tables
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# library(RSQLServer) | |
# library(RJDBC) | |
library(magrittr) | |
setGeneric("dbCreateTable", valueClass = "logical", | |
signature = c("conn", "name", "value"), | |
function(conn, name, value, ...) { | |
standardGeneric("dbCreateTable") | |
} | |
) | |
setMethod( | |
"dbCreateTable", | |
signature("SQLServerConnection"), | |
def = function(conn, name, value, key_var = NULL, char_len = 150, | |
overwrite = FALSE, verbose = TRUE) { | |
# https://github.com/imanuelcostigan/RSQLServer/blob/master/R/dbi-methods.R#L332 | |
name <- toupper(as.character(name)) | |
key_var <- as.character(key_var) | |
if (!length(key_var)) { | |
stop('Please provide primary key `key_var = "var"`.\n', | |
paste0(names(value), collapse = ", "), | |
call. = FALSE) | |
} | |
if (! (key_var %in% names(value))) { | |
stop('Cannot find "', key_var, '" in names of value') | |
} | |
dbWithTransaction(conn, { | |
found <- dbExistsTable(conn, name) | |
temp <- grepl("^#", name) | |
if ((found || temp) && overwrite) { | |
dbRemoveTable(conn, name) | |
} | |
if (found && !overwrite) { | |
stop(sprintf("There is already an object named '%s' in the database.", name), | |
" Use 'overwrite = TRUE' to force create", | |
call. = FALSE) | |
} | |
if (!found || temp || overwrite) { | |
creaet_table_sql <- sqlCreateTable(conn, name, value, row.names = FALSE) %>% | |
as.character() %>% | |
gsub("N?VARCHAR\\(\\d+\\)", sprintf("NVARCHAR(%s)", char_len), ., | |
perl = TRUE) | |
if (length(key_var)) { | |
create_pk_str <- sprintf(", CONSTRAINT PK_%s PRIMARY KEY (%s))", | |
name, | |
paste0(key_var, collapse = ", ")) | |
creaet_table_sql <- creaet_table_sql %>% | |
sub("[)]\\n?$", create_pk_str, .) | |
} | |
if (verbose) {SQL(creaet_table_sql)} | |
} | |
dbExecute(conn, creaet_table_sql) | |
}) | |
TRUE | |
} | |
) | |
setMethod( | |
"dbCreateTable", | |
signature("JDBCConnection"), | |
def = function(conn, name, value, key_var = NULL, char_len = 150, | |
overwrite = FALSE, verbose = TRUE, ...) { | |
# https://github.com/s-u/RJDBC/blob/master/R/class.R#L245 | |
ac <- .jcall(conn@jc, "Z", "getAutoCommit") | |
if (ac) { | |
.jcall(conn@jc, "V", "setAutoCommit", FALSE) | |
on.exit(.jcall(conn@jc, "V", "setAutoCommit", ac)) | |
} | |
name <- toupper(as.character(name)) | |
key_var <- as.character(key_var) | |
if (!length(key_var)) { | |
stop("Please provide primary key (character).") | |
} | |
if (! (key_var %in% names(value))) { | |
stop('Cannot find "', key_var, '" in names of value') | |
} | |
found <- dbExistsTable(conn, name) | |
temp <- grepl("^#", name) | |
if (found && !overwrite) { | |
stop(sprintf(" There is already an object named '%s' in the database.", name), | |
" Use 'overwrite = TRUE' to force create", | |
call. = FALSE) | |
} | |
if ((found || temp) && overwrite) { | |
dbRemoveTable(conn, name) | |
} | |
if (!found || temp || overwrite) { | |
creaet_table_sql <- sqlCreateTable(conn, name, value, row.names = FALSE) %>% | |
as.character() %>% | |
gsub("N?VARCHAR\\(\\d+\\)", sprintf("NVARCHAR(%s)", char_len), ., | |
perl = TRUE) | |
if (length(key_var)) { | |
create_pk_str <- sprintf(", CONSTRAINT PK_%s PRIMARY KEY (%s))", | |
name, | |
paste0(key_var, collapse = ", ")) | |
creaet_table_sql <- creaet_table_sql %>% | |
sub("[)]\\n?$", create_pk_str, .) | |
} | |
if (verbose) {SQL(creaet_table_sql)} | |
} | |
dbExecute(conn, creaet_table_sql) | |
if (ac) dbCommit(conn) | |
TRUE | |
} | |
) |
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