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Update Existing Table Data¶
Let us see how we can perform update operation to make changes to existing data inside a table.
- Typically we will have 2 clauses in update.
SETclause where the columns that are supposed to be updated.- Optional
WHEREclause where we specify the condition to filter for rows that need to be updated.
- As part of the
WHEREclause generally we will have indexed column for performance reasons.
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In [1]:
%run 05_function_get_database_connection.ipynb
In [13]:
%load_ext sql
The sql extension is already loaded. To reload it, use: %reload_ext sql
In [14]:
%env DATABASE_URL=postgresql://itversity_sms_user:itversity@pg.itversity.com:5432/itversity_sms_db
env: DATABASE_URL=postgresql://itversity_sms_user:itversity@pg.itversity.com:5432/itversity_sms_db
In [15]:
%%sql
SELECT user_id, user_role FROM users
WHERE user_id = 1
* postgresql://itversity_sms_user:***@pg.itversity.com:5432/itversity_sms_db 1 rows affected.
Out[15]:
| user_id | user_role |
|---|---|
| 1 | A |
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