How to pass variables to spark.sql query in pyspark?

Question

How to pass variables to spark.sql query in pyspark? When I query a table it fails with a AnalysisException. Why?

>>> spark.sql("select * from student").show()

+-------+--------+
|roll_no|    name|
+-------+--------+
|      1|ravindra|
+-------+--------+

>>> spark.sql("select * from student where roll_no={0} and name={1}".format(id,name)).show()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/spark-2.3.0-bin-hadoop2.6/python/pyspark/sql/session.py", line 767, in sql
    return DataFrame(self._jsparkSession.sql(sqlQuery), self._wrapped)
  File "/usr/local/spark-2.3.0-bin-hadoop2.6/python/lib/py4j-0.10.7-src.zip/py4j/java_gateway.py", line 1257, in __call__
  File "/usr/local/spark-2.3.0-bin-hadoop2.6/python/pyspark/sql/utils.py", line 69, in deco
    raise AnalysisException(s.split(': ', 1)[1], stackTrace)
pyspark.sql.utils.AnalysisException: u"cannot resolve '`ravindra`' given input columns: [default.student.id, default.student.roll_no, default.student.name]; line 1 pos 47;n'Project [*]n+- 'Filter ((roll_no#21 = 0) && (name#22 = 'ravindra))n   +- SubqueryAlias `default`.`student`n      +- HiveTableRelation `default`.`student`, org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe, [id#20, roll_no#21, name#22]n"

Asked By: Ravindra Solanki

||

Source

Answer 1

I generally use the %s string formatter inside sql strings

sqlc.sql('select * from students where roll_no=%s and name="%s"' % ('1', 'ravindra')).show()

Looking at your sql traceback, you must have missed the quotes for the name= value when ravindra is passed to the sql string, and sql engine thinks it as a variable call.

Your sql query then becomes

select * from students where roll_no=1 and name=ravindra  -- no quotes

You can adjust your sql string to

spark.sql("select * from student where roll_no={0} and name='{1}'".format(id,name)).show()

quote your {1} to get your desired result.

Answered By: samkart

How to pass variables to spark.sql query in pyspark?

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