TL;DR: My windows service wasn’t installed properly. Change the config file to point the DB to an accessible directory and reinstall the service. When trying to build a perioduc Celery task, I got the following error with Redis on Windows (running as a windows service): redis.exceptions.ResponseError: MISCONF Redis is configured to save RDB snapshots, but […]
Tag: db
Select Rows Where Value from One Column Matches Other Column
TL;DR: Use a JOIN. I’ve got a table representing a tree, using two columns:
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CREATE TABLE "EXAMPLE" ( "PROP_ID" VARCHAR2(20 BYTE) NOT NULL ENABLE, "PARENT_PROP_ID" VARCHAR2(20 BYTE) NOT NULL ENABLE, /* * Data ... */ "CLASS_ID" VARCHAR2(20 BYTE) NOT NULL ENABLE ) |
and I want to select all children for parents whose CLASS_ID have a certain value (e.g. abcd). The way I could do it was via a JOIN statement:
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SELECT * FROM EXAMPLE child JOIN EXAMPLE parent on (child.parent_prop_id = parent.prop_id) WHERE parent.class_id = 'abcd'; |
This will: Perform a join where child.parent_prop_id = parent.prop_id Filter only […]
Change a django password manually
The other day I’ve been confronted with a strange situation: I forgot the admin password for a django application. I was playing with installing my own pypi repository, I’ve configured and deployed a test application and, after a couple of weeks, I forgot the password. I tried several times bu I knew that I used […]
Add Primary Key Column to PostgreSQL Table
The other day I got a question: How to add a numeric PK column to an already existent table? A quick look on the net showed that it is indeed possible to add an auto-incrementing PK to an already existing table (if you don’t have already a PK that is!). The code is quite simple […]
Loading XSDs into Oracle through Python
Following the previous incursions in Oracle and their own documentation, we decided it was useful to attach schemas to the inserted data, just because only XML with schemas attached can be indexed. When you have some million entries, indexing seems like a good idea (once you decide what to index). In Oracle, you have DBMS_XMLSCHEMA.registerSchema() […]
MacPorts Berkley-DB 4 problem and work around
I’ve upgraded my MacPro’s hardware a bit the other day and I’ve noticed that something went bye-bye when running eclipse. Namely eclipse itself wasn’t working anymore. So I thought: What a great opportunity to do an update (eclipse, jdk…). And MacPorts. Because I wanted to upgrade my python to 2.7 (2.7 has a couple of […]