SQL translation includes vector names

[alaindanet]

filter() has an inconsistent behavior when applied to a database or a data.frame. Ideally, I would expect the same behavior.

For a database (ie sql query) filter() sends the names of the named vector, resulting in an error. filter() does not result in an error for a data.frame and returns the expected output.

library('dplyr')
#> 
#> Attachement du package : 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union
library('datasets')

con <- DBI::dbConnect(RSQLite::SQLite(), ":memory:")
copy_to(con, mtcars)

cyl_id <- mtcars %>%
  filter(carb ==1) %>%
  select(cyl) %>%
  unlist

## With df:
mtcars %>%
  filter(cyl %in% cyl_id)
#>     mpg cyl  disp  hp drat    wt  qsec vs am gear carb
#> 1  21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
#> 2  21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
#> 3  22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1
#> 4  21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1
#> 5  18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1
#> 6  24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2
#> 7  22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2
#> 8  19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4
#> 9  17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4
#> 10 32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
#> 11 30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
#> 12 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
#> 13 21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1
#> 14 27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
#> 15 26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
#> 16 30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2
#> 17 19.7   6 145.0 175 3.62 2.770 15.50  0  1    5    6
#> 18 21.4   4 121.0 109 4.11 2.780 18.60  1  1    4    2

## With db:
mtcars2 <- tbl(con, "mtcars")
mtcars2 %>%
  filter(cyl %in% cyl_id)
#> Error in result_create(conn@ptr, statement): near "AS": syntax error

# Fix:
cyl_id2 <- mtcars %>%
  filter(carb ==1) %>%
  select(cyl) %>%
  unlist(., use.names = FALSE)

mtcars2 %>%
  filter(cyl %in% cyl_id2)
#> # Source:   lazy query [?? x 11]
#> # Database: sqlite 3.22.0 [:memory:]
#>      mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear  carb
#>    <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#>  1  21       6 160     110  3.9   2.62  16.5     0     1     4     4
#>  2  21       6 160     110  3.9   2.88  17.0     0     1     4     4
#>  3  22.8     4 108      93  3.85  2.32  18.6     1     1     4     1
#>  4  21.4     6 258     110  3.08  3.22  19.4     1     0     3     1
#>  5  18.1     6 225     105  2.76  3.46  20.2     1     0     3     1
#>  6  24.4     4 147.     62  3.69  3.19  20       1     0     4     2
#>  7  22.8     4 141.     95  3.92  3.15  22.9     1     0     4     2
#>  8  19.2     6 168.    123  3.92  3.44  18.3     1     0     4     4
#>  9  17.8     6 168.    123  3.92  3.44  18.9     1     0     4     4
#> 10  32.4     4  78.7    66  4.08  2.2   19.5     1     1     4     1
#> # … with more rows

# Because the sql request send names and the values: 
my_query <- mtcars2 %>%
  filter(cyl %in% cyl_id)
my_query %>% show_query
#> <SQL>
#> SELECT *
#> FROM `mtcars`
#> WHERE (`cyl` IN (4.0 AS "cyl1", 6.0 AS "cyl2", 6.0 AS "cyl3", 4.0 AS "cyl4", 4.0 AS "cyl5", 4.0 AS "cyl6", 4.0 AS "cyl7"))

Created on 2019-03-22 by the [reprex package](http://reprex.tidyverse.org) (v0.2.0.9000).

Thank you very much for this package (and the others)!

[hadley]

Minimal reprex:

library(dbplyr)
translate_sql(x %in% c(a = 1, b = 2))
#> <SQL> `x` IN (1.0 AS `a`, 2.0 AS `b`)

^{Created on 2019-03-22 by the reprex package (v0.2.1.9000)}