a6b8182006
## What changes were proposed in this pull request? The Antlr lexer we use to tokenize a SQL string may wrongly tokenize a fully qualified identifier as a decimal number token. For example, table identifier `default.123_table` is wrongly tokenized as ``` default // Matches lexer rule IDENTIFIER .123 // Matches lexer rule DECIMAL_VALUE _TABLE // Matches lexer rule IDENTIFIER ``` The correct tokenization for `default.123_table` should be: ``` default // Matches lexer rule IDENTIFIER, . // Matches a single dot 123_TABLE // Matches lexer rule IDENTIFIER ``` This PR fix the Antlr grammar so that it can tokenize fully qualified identifier correctly: 1. Fully qualified table name can be parsed correctly. For example, `select * from database.123_suffix`. 2. Fully qualified column name can be parsed correctly, for example `select a.123_suffix from a`. ### Before change #### Case 1: Failed to parse fully qualified column name ``` scala> spark.sql("select a.123_column from a").show org.apache.spark.sql.catalyst.parser.ParseException: extraneous input '.123' expecting {<EOF>, ... , IDENTIFIER, BACKQUOTED_IDENTIFIER}(line 1, pos 8) == SQL == select a.123_column from a --------^^^ ``` #### Case 2: Failed to parse fully qualified table name ``` scala> spark.sql("select * from default.123_table") org.apache.spark.sql.catalyst.parser.ParseException: extraneous input '.123' expecting {<EOF>, ... IDENTIFIER, BACKQUOTED_IDENTIFIER}(line 1, pos 21) == SQL == select * from default.123_table ---------------------^^^ ``` ### After Change #### Case 1: fully qualified column name, no ParseException thrown ``` scala> spark.sql("select a.123_column from a").show ``` #### Case 2: fully qualified table name, no ParseException thrown ``` scala> spark.sql("select * from default.123_table") ``` ## How was this patch tested? Unit test. Author: Sean Zhong <seanzhong@databricks.com> Closes #15006 from clockfly/SPARK-17364. |
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antlr4/org/apache/spark/sql/catalyst/parser | ||
java/org/apache/spark/sql | ||
scala/org/apache/spark/sql |