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Antlr4 is a parser generator for reading, processing and executing text, there are severaltarget languages (Java, Python, JavaScript, Dart) available. CrateDB uses the Java target.

The repository holds libraries/packages created from some of those available languages, sofar:Python andJavaScript. More might be added if needed in the future.

These libraries allow you to parse Crate's SQL dialect without sending it to a CrateDB instance.

• Python:https://github.com/crate/cratedb-sqlparse/tree/main/cratedb_sqlparse_py
• Javascript:https://github.com/crate/cratedb-sqlparse/tree/main/cratedb_sqlparse_js

You can install the package in both its Python and JavaScript variants.

• https://pypi.org/project/cratedb-sqlparse/
• https://www.npmjs.com/package/@cratedb/cratedb-sqlparse

pip install cratedb-sqlparse

npm install @cratedb/cratedb-sqlparse

fromcratedb_sqlparseimportsqlparsequery="""    SELECT * FROM SYS.SHARDS;    INSERT INTO doc.tbl VALUES (1);"""statements=sqlparse(query)select_query=statements[0]print(select_query.query)# 'SELECT * FROM SYS.SHARDS'

All the implemented libraries can validate SQL, split queries and parse using antrl4's listeners.

Listeners are partially implemented, which means that we can only parse:

• Create table statements: table name, schema, and 'with' options

If more metadata is needed, it can be requested in a new issue.

New features should preferably be implemented in all available targets.

The target language has to be available in antlr4,seehttps://github.com/antlr/antlr4/blob/master/doc/targets.md.

Add the new target and paths to the build script, seesetup_grammar.py.

There are several features that would need to be implemented, like case-insensitive input stream, nativeexceptions as error listener, dollar-strings and any new one. See past commits to see how they wereimplemented in Python and Javascript, remember thatCrateDB'S SQLParser written in Java is the mostcomplete and the default reference.

The generated parser is not uploaded to the repository because it is huge.To use the package locally or to build a different version use the build script.Further information can be found in thedeveloper guide.