I do some search in: PostgreSQL: https://www.postgresql.org/docs/9.1/sql-syntax-lexical.html ----> don't support SqlServer: https://docs.microsoft.com/en-us/sql/relational-databases/databases/database-identifiers?view=sql-server-ver15 ---->don't support Oracle: https://docs.oracle.com/javadb/10.6.2.1/ref/crefsqlj1003454.html ----->don't support
So If we need to support this. The Babel module is appropriate. Ruben Q L <rube...@gmail.com> 于2022年2月16日周三 18:31写道： > Hello XuRenhe, > > Please be aware that our dev list does not allow images. > > Regarding your question, I found this on the SQL standard: > > « An <identifier start> is any character in the Unicode General Category > classes “Lu”, “Ll”, “Lt”, “Lm”, “Lo”, or “Nl”. > NOTE 95 — The Unicode General Category classes “Lu”, “Ll”, “Lt”, “Lm”, > “Lo”, and “Nl” are assigned to Unicode characters that are, respectively, > upper-case letters, lower case letters, title-case letters, modifier > letters, other letters, and letter numbers. » > > In case it helps, I found in Wikipedia a link to an older version of the > standard [1] which basically says the same thing (page 85). > > To sum up, identifiers must start with a letter, so Calcite is respecting > the standard (and it seems MySql deviates from it). > > I am not sure if this is something that could (or should) be achieved with > the Calcite SqlDialect mechanism; I am not very familiar with it, maybe > someone else can provide more information. > > Best regards, > Ruben > > [1] http://www.contrib.andrew.cmu.edu/~shadow/sql/sql1992.txt > > > On Wed, Feb 16, 2022 at 8:18 AM 徐仁和 <xurenhe19910...@gmail.com> wrote: > > > Hi community: > > > > Parsing sql fails, when meeting the identifier starting with number. > > > > Here, test case: > > // org.apache.calcite.test.SqlToRelConverterTest > > @Test void testIdentifierStartWithNumber() { > > final String sql = > > "select 1_c1 from (select deptno as 1_c1 from emp)"; > > sql(sql).ok(); > > } > > > > It throws an exception as below: > > java.lang.RuntimeException: > > org.apache.calcite.sql.parser.SqlParseException: Encountered "1" at line > 1, > > column 36. > > Was expecting one of: > > <QUOTED_STRING> ... > > <BRACKET_QUOTED_IDENTIFIER> ... > > <QUOTED_IDENTIFIER> ... > > <BACK_QUOTED_IDENTIFIER> ... > > <BIG_QUERY_BACK_QUOTED_IDENTIFIER> ... > > <HYPHENATED_IDENTIFIER> ... > > <IDENTIFIER> ... > > <UNICODE_QUOTED_IDENTIFIER> ... > > > > at > > > org.apache.calcite.sql.parser.SqlParseException.writeReplace(SqlParseException.java:171) > > > > *Mysql supports this case, should calcite support it?* > > > > *Failed png in Calcite:* > > [image: image.png] > > > > *Successful png in MySql:* > > [image: image.png] > > > > > > > > Best XuRenhe > > > > >
