[BUG] JSQLParser 4.9: pgvector cosine similarity <=> Failing

[lqh19870820]

Failing SQL Feature:

• Crash in Postgres Vector when evaluating cosine similarity like (embedding <=> '[3,1,2]') due to enclosing parentheses. <=> can't be parsed

SQL Example:

• Using

  Statement statement = CCJSqlParserUtil.parse(vectorSql)

however, the following crashes:

String vectorSql= "SELECT (embedding <=> '[3,1,2]') AS cosine_similarity FROM items;";

with error message:

Exception in thread "main" net.sf.jsqlparser.JSQLParserException: net.sf.jsqlparser.parser.ParseException: Encountered unexpected token: "<=" <OP_MINORTHANEQUALS>
at line 1, column 19.

Was expecting one of:

")"
"."
"::"
"["
"^"

at net.sf.jsqlparser.parser.CCJSqlParserUtil.parseStatement(CCJSqlParserUtil.java:350)
at net.sf.jsqlparser.parser.CCJSqlParserUtil.parse(CCJSqlParserUtil.java:123)
at net.sf.jsqlparser.parser.CCJSqlParserUtil.parse(CCJSqlParserUtil.java:89)
at net.sf.jsqlparser.parser.CCJSqlParserUtil.parse(CCJSqlParserUtil.java:62)
at cn.xlink.codeless.data.worker.restful.test.SqlTest.parseInsert(SqlTest.java:293)
at cn.xlink.codeless.data.worker.restful.test.SqlTest.main(SqlTest.java:71)

Caused by: java.util.concurrent.ExecutionException: net.sf.jsqlparser.parser.ParseException: Encountered unexpected token: "<=" <OP_MINORTHANEQUALS>
at line 1, column 19.