feat: improve pgsql grammar and add unit tests(#201)
* feat(pgsql: upgrade keywords and refresh them to parser file): pgsql
* feat(pgsql: check create table's syntax): pgsql
* feat(pgsql: check and update drop syntax): pgsql: check and update drop syntax
* feat: pgsql: check create's sql syntax and update g4 file
* feat: pgsql:complete other's sql and syntax except select, insert, drop
* feat: pgsql: update create, delete, insert, select, update and others' syntax
* test: pgsql: update alter's sql
* feat: pgsql: update syntax g4 file
* feat: pgsql: upgrade keywords to without '_P' in lexer and parser file
* docs: pgsql: update copyright and Reference of parser and lexer
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Co-authored-by: zhaoge <>
2e6d18e7dc