Simple-ddl-parser-2

Improvements
1. Fixed bug with places first table property value in 'authorization' key. Now it is used real property name.
2. Fixed typo on Databricks dialect
3. improved equals symbols support within COMMENT statement.
4. turn regexp into functions

MySQL Improvements
1. UNSIGNED property after int parsed validly now

Snowflake
1. Snowflake TAG now available on SCHEMA definitions.

Minor Fixes
1. When using `normalize_names=True` do not remove `[]` from types like `decimal(21)[]`.
2. When using `normalize_names=True` ensure that `"complex"."type"` style names convert to `complex.type`.

In output structure was done important changes that can in theory breaks code.

Important changes
1. Important change:

all custom table properties that are defined after column definition in 'CREATE TABLE' statement and relative to only one dialect (only for SparkSQL, or HQL,etc), for example, like here:
https://github.com/xnuinside/simple-ddl-parser/blob/main/tests/dialects/test_snowflake.py#L767 or https://github.com/xnuinside/simple-ddl-parser/blob/main/tests/dialects/test_spark_sql.py#L133 will be saved now in property `table_properties` as dict.
Previously they was placed on same level of table output as `columns`, `alter`, etc. Now, they grouped and moved to key `table_properties`.

2. Formatting parser result now represented by 2 classes - Output & TableData, that makes it more strict and readable.

3. The output mode now functions more strictly. If you want to obtain output fields specific to a certain dialect,
use output_mode='snowflake' for Snowflake or output_mode='hql' for HQL, etc.
Previously, some keys appeared in the result without being filtered by dialect.
For example, if 'CLUSTER BY' was in the DDL, it would show up in the 'cluster_by' field regardless of the output mode.
However, now all fields that only work in certain dialects and are not part of the basic SQL notation will only be shown
if you choose the correct output_mode.


New Dialects support
1. Added as possible output_modes new Dialects:
- Databricks SQL like 'databricks',
- Vertica as 'vertica',
- SqliteFields as 'sqlite',
- PostgreSQL as 'postgres'

Full list of supported dialects you can find in dict - `supported_dialects`:

`from simple_ddl_parser_2 import supported_dialects`

Currently supported: ['redshift', 'spark_sql', 'mysql', 'bigquery', 'mssql', 'databricks', 'sqlite', 'vertics', 'ibm_db2', 'postgres', 'oracle', 'hql', 'snowflake', 'sql']

If you don't see dialect that you want to use - open issue with description and links to Database docs or use one of existed dialects.

Snowflake updates:
1. For some reasons, 'CLONE' statement in SNOWFLAKE was parsed into 'like' key in output. Now it was changed to 'clone' - inner structure of output stay the same as previously.

MySQL updates:
1. Engine statement now parsed correctly. Previously, output was always '='.

BigQuery updates:
1. Word 'schema' totally removed from output. `Dataset` used instead of `schema` in BigQuery dialect.

Minor Fixes
1. Removed debug print

Improvements
1. Added support for several ALTER statements (ADD, DROP, RENAME, etc) - https://github.com/xnuinside/simple-ddl-parser/issues/215
In 'alter' output added several keys:
1. 'dropped_columns' - to store information about columns that was in table, but after dropped by alter
2. 'renamed_columns' - to store information about columns that was renamed
3. 'modified_columns' - to track alter column changes for defaults, datetype, etc. Argument stores previous columns states.

Fixes
1. Include source column names in FOREIGN KEY references. Fix for: https://github.com/xnuinside/simple-ddl-parser/issues/196
2. ALTER statement now will be parsed correctly if names & schemas written differently in `create table` statement and alter.
For example, if in create table you use quotes like "schema_name"."table_name", but in alter was schema_name.table_name - previously it didn't work, but now parser understand that it is the same table.

Improvements
Snowflake update:
1. Added support for Snowflake Virtual Column definition in External Column `AS ()` statement - https://github.com/xnuinside/simple-ddl-parser/issues/218
2. enforce support for Snowflake _FILE_FORMAT options in External Column ddl statement - https://github.com/xnuinside/simple-ddl-parser/issues/221

Others
1. Support for KEY statement in CREATE TABLE statements. KEY statements will now create INDEX entries in the DDL parser.