Useful tips for everyday
Why is Inner join slower than LEFT JOIN? A LEFT JOIN is absolutely not faster than an INNER JOIN . In fact, it’s slower; by…
How to download and install PostGIS? Run the “StackBuilder” utility and install the PostGIS add-on. If you want to use the zip, setup, and setup…
How to display multiple fields in a JSON query? It’s jumbled up. My query displays all the first names first, and then all the last…
How do I select non distinct rows in SQL? select count(distinct NAME) from MYTABLE. The result was…248025. Query2: SELECT * FROM MYTABLE WHERE NAME IN(SELECT…
Can a table have more than one foreign key? A table may have multiple foreign keys, and each foreign key can have a different parent…
How do I create a backup schedule in SQL? In Task Scheduler, right-click on Task Schedule Library and click on Create Basic task…. Enter the…
How do I combine two update queries in SQL? How to use multiple tables in SQL UPDATE statement with JOIN CREATE TABLE table1 (column1 INT,…
How do I limit a query in MongoDB? To specify the limit: In the Query Bar, click Options. Enter an integer representing the number of…
How do you deal with target leakage? The following actions may help prevent target leakage: Cross validation – for time series this means selecting data…
What is performance in neural network? for Artificial Neural Network Models* In addition to trained ANN validation, this performance measure is often used to evaluate…