This displays the column definitions along with the comments, if any. This can be verified using “SHOW FULL COLUMNS FROM table_name” command. To add a new column to an existing table, you use the ALTER TABLE ADD COLUMN statement as follows: ALTER TABLE table ADD COLUMN columnname columndefinition FIRST AFTER existingcolumn Code language: SQL (Structured Query Language) (sql) Let’s examine the statement in more detail. The above code adds a comment to the column “Address” the table. Query="ALTER TABLE Students MODIFY Address VARCHAR(100) COMMENT "This is the column to store address."" import nnectorĭb=(host="your host", user="your username", password="your We need to add a comment to this column to specify that this is the address column. Database is 15 Gig and there are about 6 instances of the database running on cloud server with 32 gigs of ram. When I tried: ALTER TABLE mytable ADD COLUMN my column varchar (255) DEFAULT '' NULL It completes much faster (in a matter of seconds) and works 100 of the time. We have a column named “addr” of type VARCHAR(50). I had to restart the MySQL several times to get it to complete. Suppose we have a table named “Students”. Steps to add comment to acolumn in a table using MySQL in pythonĮstablish connection with the connector using connect()Ĭreate the cursor object using cursor() methodĬreate a query using the appropriate mysql statementsĮxecute the SQL query using execute() method The your_comment is the comment you wish to add to that particular column. The column_name and column_definition specify the name and datatype of the column. Here, the table_name specifies the name of the table. MODIFY column_name column_definition COMMENT “your_comment” The ALTER statement along with the MODIFY command and COMMENT clause is used to add comments to a column. The comments can be added in the columns using the ALTER command. While specifying the collation to the table you have been careful about the table. If some other person is viewing and working on that table, he can get idea about the columns are all about. ![]() These comments will explain the function or tell something about the column. We can add comments to columns in a sql table. These are just for the explanatory purpose and are of great importance. The comments are ignored by the compilers and are not executed. ![]() This enables the outside person to understand the need and use of that particular code. The comments in the code are provided to explain the purpose of the code staement used. A comment is a readable explanation provided about something.
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