Alter table to add/update multiple column comments

[bharathjs]

I was wondering if there's a way to alter table and add/update comments for multiple columns at once using SQL or API calls. For instance - 

ALTER TABLE <table_name> CHANGE COLUMN <col1> COMMENT '<comment1>',

CHANGE COLUMN <col2> COMMENT 'comment2' ; 

I would like to update column comments for multiple tables for over 200 fields and flexible using sql, pyspark, apis. Would be great if there is a way to achieve this. Thanks in advance...   

[filipniziol]

Hi, assuming you have a dictionary with column name to comment mapping, you can do this using pyspark like this:

columns_comments = {
    "col1": "comment1",
    "col2": "comment2",
    # Add all your columns and comments here
}

for col, comment in columns_comments.items():
    spark.sql(f"ALTER TABLE your_table_name CHANGE COLUMN {col} SET COMMENT '{comment}'")

[bharathjs]

Yeah I did consider this approach but one drawback I observed with this approach is it takes a while to updated comments for ~200 columns. I'm looking for more reliable solution to update column's comments concurrently.