The GROUP BY clause will split the result set into groups based on the language column. The HAVING clause will pick only those languages that occur more than once: This way, you can find the duplicate rows using the COUNT() function. How to Delete Duplicates in Postgres Using a DELETE USI...
PostgreSQL is a powerful relational database management system. One of its standout features is its ability to handle unstructured data by allowing you to store it in a JSON column. This means you can enjoy the benefits of a structured relational database while leveraging the flexibility of JSON...
If you also want to disallow empty values ( '' is something different than 'NULL') you would need to change the condition to where coalesce(email, '') = '') But the trigger approach is wrong to begin with: you should declare the email column as NOT NULL and then ...
How to Rename a Column in Postgres? A table column inPostgreSQLcan be renamed/modified using the"ALTER TABLE"command: ALTER TABLE tbl_name RENAME old_col_name TO new_col_name; - Here,ALTER TABLEis a command used to alter a table inPostgreSQL. -RENAMEandTOare predefined clauses used to ...
Using Postgres sometimes feels like magic. But sometimes the magic is too much, such as when you are trying to understand the reason behind a seemingly bad Postgres query plan. I've often times found myself in a situation where I asked myself:"Postgres, what are you thinking?". Staring ...
In Postgres, I set out to write a SQL statement that would return various fields from one table, along with a column containing an array of tag strings that come from another table. I've made quite good progress with this code: SELECT p.photo_id, p.name, p.path, array_agg(t.tag)...
ALTER TABLE pg_equipment DROP COLUMN working_order; We can rename the entire table with this command: ALTER TABLE pg_equipment RENAME TO playground_equip; Deleting Tables in PostgreSQL We can delete the table we created by typing: DROP TABLE playground_equip; ...
I've created a custom object to get the result of an Raw SQL. I used JSONB to aggregate some data. The object is defined like this: modelBuilder.Entity<PermissionWithScopesByPropertyDto>(entity => { entity.HasNoKey(); entity.Property(e =...
Note: If you wish to check duplicates in thesagecolumn, replace it with thesnamecolumn in the query. In addition, if you wish to find a duplicate record with the same name and age, add both columns to the query. If you are well versed with nested queries, this might be an easy solut...
To remove a Postgres sequence, execute the “DROP SEQUENCE” command followed by the sequence name to be dropped.