I use loopback with a postgrsql database. In my database I have a trigger function to automatically fill some columns.
Is it possible with loopback to retrieve the values create by the database trigger in a after save event?
Is there an equivalent to SQL "returning" in loopback?
Related
What is the equivalent of sp_refreshsqlmodule (sys stored procedure) in SQL Server for PostgreSQL?
sp_refreshsqlmodule
https://learn.microsoft.com/en-us/sql/relational-databases/system-stored-procedures/sp-refreshsqlmodule-transact-sql?view=sql-server-ver15
Updates the metadata for the specified non-schema-bound stored
procedure, user-defined function, view, DML trigger, database-level
DDL trigger, or server-level DDL trigger in the current database.
Persistent metadata for these objects, such as data types of
parameters, can become outdated because of changes to their underlying
objects.
In Postgres views, procedures and functions are created in a similar way as SQL Server's "with schema binding".
So there is no equivalent procedure in Postgres, because there is no need for it.
I tried searching for it but couldn't find out
What is the best way to copy data from Redshift to Postgresql Database ?
using Talend job/any other tool/code ,etc
anyhow i want to transfer data from Redshift to PostgreSQL database
also,you can use any third party database tool if it has similar kind of functionality.
Also,as far as I know,we can do so using AWS Data Migration Service,but not sure our source db and destination db matches that criteria or not
Can anyone please suggest something better ?
The way I do it is with a Postgres Foreign Data Wrapper and dblink,
This way, the redshift table is available directly within Postgres.
Follow the instructions here to set it up https://aws.amazon.com/blogs/big-data/join-amazon-redshift-and-amazon-rds-postgresql-with-dblink/
The important part of that link is this code:
CREATE EXTENSION postgres_fdw;
CREATE EXTENSION dblink;
CREATE SERVER foreign_server
FOREIGN DATA WRAPPER postgres_fdw
OPTIONS (host '<amazon_redshift _ip>', port '<port>', dbname '<database_name>', sslmode 'require');
CREATE USER MAPPING FOR <rds_postgresql_username>
SERVER foreign_server
OPTIONS (user '<amazon_redshift_username>', password '<password>');
For my use case I then set up a postgres materialised view with indexes based upon that.
create materialized view if not exists your_new_view as
SELECT some,
columns,
etc
FROM dblink('foreign_server'::text, '
<the redshift sql>
'::text) t1(some bigint, columns bigint, etc character varying(50));
create unique index if not exists index1
on your_new_view (some);
create index if not exists index2
on your_new_view (columns);
Then on a regular basis I run (on postgres)
REFRESH MATERIALIZED VIEW your_new_view;
or
REFRESH MATERIALIZED VIEW CONCURRENTLY your_new_view;
In the past, I managed to transfer data from one PostgreSQL database to another by doing a pg_dump and piping the output as an SQL command to the second instance.
Amazon Redshift is based on PostgreSQL, so this method should work, too.
You can control whether pg_dump should include the DDL to create tables, or whether it should just load the data (--data-only).
See: PostgreSQL: Documentation: 8.0: pg_dump
I have a UDF function in Cosmos DB , it takes a parameter and returns the documents that meets the condition based on the parameter.
Each document returned by this UDF has 3 fields,
Customer ID
Modified Date
Customer Status
I need this information in a SQL Server SP present in another database.
I am thinking of having a powershell script to bring this data from the Cosmos DB , store it in a table local to the SQL server database , and then use this table eventually in the SP.
I wondering if my above approach to fetch data from Cosmos DB to SQL Server database is right, and if so could I know if we can execute a cosmos DB UDF from a powershell script and use the result set returned by the UDF.
Based on your description,maybe you could use Azure Data Factory.
Step1: Follow the article to create Copy activity.
Step2: Configure Cosmos db source data:
sql:
SELECT udf.adf(c.fields).CustomerID,
udf.adf(c.fields).ModifiedDate,
udf.adf(c.fields).CustomerStatus FROM c
Then,please follow the steps from this doc:
Step 3: Configure your Sink dataset:
Step 4: Configure Sink section in copy activity as follows:
Step 5: In your database, define the table type with the same name as sqlWriterTableType. Notice that the schema of the table type should be same as the schema returned by your input data.
CREATE TYPE [dbo].[CsvType] AS TABLE(
[ID] [varchar](256) NOT NULL,
[Date] [varchar](256) NOT NULL,
[Status ] [varchar](256) NOT NULL
)
Step 6: In your database, define the stored procedure with the same name as SqlWriterStoredProcedureName. It handles input data from your specified source, and merge into the output table. Notice that the parameter name of the stored procedure should be the same as the "tableName" defined in dataset.
Create PROCEDURE convertCsv #ctest [dbo].[CsvType] READONLY
AS
BEGIN
MERGE [dbo].[adf] AS target
USING #ctest AS source
ON (1=1)
WHEN NOT MATCHED THEN
INSERT (id,data,status)
VALUES (source.ID,source.Date,source.Status );
END
I have been working on my code for our activity in our major comp sci subject. The task asks to update a certain field in the table in postgresql using stored procedure
I have already create a gettopemp() to retrieved the data in the table, and I want to retrieve the information of gettopemp() to my new stored procedure updatetopemp(). How to use stored procedure inside the stored procedure ???
If you want to pass a function name as a parameter and call that in your code, you'll have to use dynamic SQL.
I am seeking suggestions on methods to trigger the running of code based on specific event occurring.
Basically I need to monitor all inserts into a table and compare a column value against a parameter set in another table.
For example, when a new record is added to the table and the column [Temperature] is greater than 30 (which is a value set in another table). Send an alert email to notify of this situation.
You can create a trigger (special type of stored procedure) that is automatically executed after an insert happened. Documentation for triggers is here: https://technet.microsoft.com/en-us/library/ms189799(v=sql.120).aspx
You will not be able to send an email out of SQL Database though.
Depending on how quick you need the notification after the insert, maybe you could make an insert into yet another table from within the trigger and query this new table periodically (e.g. using a script in Azure automation) and have the email logic outside the database.