我有一个问题:我在R中测试了CASE WHEN SQL查询,但得到了一个错误。请您,提出一个解决方案?
下面是重现的代码。
library(sparklyr)
library(gapminder)
spark_conn <- spark_connect(master = "local")
data("gapminder")
copy_to(spark_conn, gapminder)
src_tbls(spark_conn)
#The query gave an error
DBI::dbGetQuery(spark_conn, "
SELECT *
CASE WHEN pop > 100000000 THEN 'Biggy'
WHEN pop < 10000000 THEN 'Small'
ELSE 'Medium' END
AS pop_category
FROM gapminder
WHERE year = 1957
")
Error: org.apache.spark.sql.catalyst.parser.ParseException:
mismatched input 'WHEN' expecting <EOF>(line 3, pos 21)
== SQL ==
SELECT *
CASE WHEN pop > 10000000 THEN 'Biggy'
---------------------^^^
WHEN pop < 10000000 THEN 'Small'
ELSE 'Medium' END
AS pop_category
FROM gapminder
你少了一个逗号 ,
之后 *
...只要在后面加上逗号,你的查询就可以了。
SELECT *,
CASE WHEN pop > 100000000 THEN 'Biggy'
WHEN pop < 10000000 THEN 'Small'
ELSE 'Medium' END
AS pop_category
FROM gapminder
WHERE year = 1957