SQL queries to alter the table structure.
Add Column
ALTER TABLE TableName
ADD FieldName varchar(255);
Drop Column
ALTER TABLE TableName
DROP COLUMN FieldName;
Rename column
ALTER TABLE TableName
RENAME COLUMN OldName to NewName;
Alter/Change column data type
ALTER TABLE TableName
ALTER COLUMN ColumnName varchar(255);
Source
https://www.w3schools.com/SQl/sql_alter.asp
