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Author: Simo
Looking for the build forest (with recursive, postgreSQL 9.5)
I have a table of identities (ie aliases) for any number of people. Each row has a previous name and a new name. In production, there are approximately 1M rows. For example:
id, old, new
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PostgreSQL – Columns must appear in Group BY clauses or for polymeric functions
I am updating the Qt software to make it compatible with SQLite and PostgreSQL.
I have a C method for calculating the elements of a given table of a given sub-sentence. < /p> In SQLite, the follow
TIDB source reading series articles (1)
At TiDB DevCon2018, we announced the TiDB source code reading and sharing activity, and promised to publish a series of articles and videos to help everyone understand the TiDB source code. Everyon
PostgreSQL – Postgres Query Optimization
Below are two almost identical postgres queries, but produced very different query plans and execution times. I assume that the first query is fast because form_id =’W40′ is only 196 Form_instance
PostgreSQL – Reset ID count after table deletion ()
For testing purposes, I clear (delete) each table before executing the code.
for table in reversed (db.metadata.sorted_tables):
engine.execute(table.delete())
do_stuff() However, the id valu
NOSQL – Cassandra column key automatically increment
I am trying to understand Cassandra and how to build my column family (CF), but since I am used to relational databases, it is difficult.
For example , If I create a simple user CF and I try
Running errors in PostgreSQL
CREATE OR REPLACE FUNCTION msgfailerror() RETURNS trigger AS
‘ BEGIN
IF NEW.noces< new.first_column THEN
RAISE EXCEPTION ' cannot have a negative salary';
END IF;
return new;
END' LANGUAG
PostgreSQL – PLPGSQL function returns another function value
I have a function func1() that returns integers.
I want to write another function func2 (mode integer), which can return func1()reults Or do more things. The return value of func1() is INTEGE
Add a missing monthly date in the time series data in PostgreSQL
I have monthly time series data in the table, where the date is the last day of the month. Some dates are missing in the data. I want to insert these dates and add zero values for other attribute