added options immedate & replace to eng_SQL

R/engine.R

@@ -560,13 +560,14 @@ is_sql_update_query = function(query) {
   grepl('^\\s*(INSERT|UPDATE|DELETE|CREATE|DROP).*', query, ignore.case = TRUE)
 }
 
+
 # sql engine
 eng_sql = function(options) {
   # return chunk before interpolation eagerly to avoid connection option check
   if (isFALSE(options$eval) && !isTRUE(options$sql.show_interpolated)) {
     return(engine_output(options, options$code, ''))
   }
-
+  
   # Return char vector of sql interpolation param names
   varnames_from_sql = function(conn, sql) {
     varPos = DBI::sqlParseVariables(conn, sql)
@@ -575,27 +576,27 @@ eng_sql = function(options) {
       sub('^\\?', '', varNames)
     }
   }
-
+  
   # Vectorized version of exists
   mexists = function(x, env = knit_global(), inherits = TRUE) {
     vapply(x, exists, logical(1), where = env, inherits = inherits)
   }
-
+  
   # Interpolate a sql query based on the variables in an environment
   interpolate_from_env = function(conn, sql, env = knit_global(), inherits = TRUE) {
     names = unique(varnames_from_sql(conn, sql))
     names_missing = names[!mexists(names, env, inherits)]
     if (length(names_missing) > 0) {
       stop("Object(s) not found: ", paste('"', names_missing, '"', collapse = ", "))
     }
-
+    
     args = if (length(names) > 0) setNames(
       mget(names, envir = env, inherits = inherits), names
     )
-
+    
     do.call(DBI::sqlInterpolate, c(list(conn, sql), args))
   }
-
+  
   # extract options
   conn = options$connection
   if (is.character(conn)) conn = get(conn, envir = knit_global())
@@ -608,13 +609,26 @@ eng_sql = function(options) {
     max.print = -1
   sql = one_string(options$code)
   params = options$params
-
+  immediate=  F
+  if(isTRUE(options$immediate)) {
+    immediate= T
+    replace=  F
+    if(isTRUE(options$replace)) {
+        replace= T
+        reptable =  gsub('(^.*into[[:space:]]+)(#.+)([[:space:]]+from.*$)', '\\2', sql, ignore.case = T)
+        if(sub('(.).*.$', '\\1', reptable) != '#') stop2(
+          "To replace a table, the table has to be a temporary table (tablename staring with # or ##)."
+        )
+        sql <- paste0("if object_id('tempdb.dbo.", reptable, "') is not null drop table ", reptable, " ;", sql)
+    }
+  }
+
   query = interpolate_from_env(conn, sql)
   if (isFALSE(options$eval)) return(engine_output(options, query, ''))
-
+  
   data = tryCatch({
     if (is_sql_update_query(query)) {
-      DBI::dbExecute(conn, query)
+      DBI::dbExecute(conn, query, immediate = immediate)
       NULL
     } else if (is.null(varname) && max.print > 0) {
       # execute query -- when we are printing with an enforced max.print we
@@ -623,50 +637,50 @@ eng_sql = function(options) {
       data = DBI::dbFetch(res, n = max.print)
       DBI::dbClearResult(res)
       data
-
+      
     } else {
       if (length(params) == 0) {
-        DBI::dbGetQuery(conn, query)
+        DBI::dbGetQuery(conn, query, immediate = immediate)
       } else {
         # If params option is provided, parameters are not interplolated
-        DBI::dbGetQuery(conn, sql, params = params)
+        DBI::dbGetQuery(conn, sql, immediate = immediate, params = params)
       }
     }
   }, error = function(e) {
     if (!options$error) stop(e)
     e
   })
-
+  
   if (inherits(data, "error"))
     return(engine_output(options, query, one_string(data)))
-
+  
   # create output if needed (we have data and we aren't assigning it to a variable)
   output = if (length(dim(data)) == 2 && ncol(data) > 0 && is.null(varname)) capture.output({
-
+    
     # apply max.print to data
     display_data = if (max.print == -1) data else head(data, n = max.print)
-
+    
     # get custom sql print function
     sql.print = opts_knit$get('sql.print')
-
+    
     # use kable for markdown
     if (!is.null(sql.print)) {
       options$results = 'asis'
       cat(sql.print(data))
     } else if (out_format('markdown')) {
-
+      
       # we are going to output raw markdown so set results = 'asis'
       options$results = 'asis'
-
+      
       # force left alignment if the first column is an incremental id column
       first_column = display_data[[1]]
       if (is.numeric(first_column) && length(first_column) > 1 && all(diff(first_column) == 1))
         display_data[[1]] = as.character(first_column)
-
+      
       # wrap html output in a div so special styling can be applied
       add_div = is_html_output() && getOption('knitr.sql.html_div', TRUE)
       if (add_div) cat('<div class="knitsql-table">\n')
-
+      
       # determine records caption
       caption = options$tab.cap
       if (is.null(caption)) {
@@ -680,27 +694,27 @@ eng_sql = function(options) {
       }
       # disable caption
       if (identical(caption, NA)) caption = NULL
-
+      
       # print using kable
       print(kable(display_data, caption = caption))
-
+      
       # terminate div
       if (add_div) cat("\n</div>\n")
-
+      
       # otherwise use tibble if it's available
     } else if (loadable('tibble')) {
       print(tibble::as_tibble(display_data), n = max.print)
-
+      
     } else print(display_data) # fallback to standard print
   })
   if (options$results == 'hide') output = NULL
-
+  
   # assign varname if requested
   if (!is.null(varname)) assign(varname, data, envir = knit_global())
-
+  
   # reset query to pre-interpolated if not expanding
   if (!isTRUE(options$sql.show_interpolated)) query <- options$code
-
+  
   # return output
   engine_output(options, query, output)
 }