![]() If my domain name was, then my databases would be something like mynewdom_database1. I work on a shared hosting service provider that asigns the database schemas’s name (MySQL DATABASE) tied to the hosting name. Finally I ended up with something odd, for what I have to elaborate about my query: Since I had no useful debugging information (as the error was at saving time, I wasn’t even able to build the app nor to execute it), I tried to simplify my query and “complex” it step by step. I practically don’t know a thing about PDO implementation and behaviour on PHP, but if the query works, how Scriptcase handles the queries? Didn’t it only take the result of the PDO execution of the SQL on the server? Why is Scriptcase crashing with a working query, even when it supports the UNION structure? I tested my query and it works, but when I use it to create a Grid app, scriptcase crashes even the saving process (a pop up shows up and It looses any field in the app) INNER JOIN myOtherTable AS T2 ON T1.col1 = T2.col1ĪFAIK, the first statement returns only 3 columns, as well as the second one. I want to create a grid with a MySQL UNION sentence of two SELECT statements, but one of them has some INNER JOIN statements and explicitly retrieves the same type and amount of columns something like this: (SELECT For example, you can filter them differently using different WHERE clauses.I have a running grid with a MySQL sentence that unites a single constant row with a regular select statement somehitng like this: (SELECT ![]() Since you are writing two separate SELECT statements, you can treat them differently before appending. This is because most of the instances in which you'd want to use UNION involve stitching together different parts of the same dataset (as is the case here). ![]() While the column names don't necessarily have to be the same, you will find that they typically are. The columns must have the same data types in the same order as the first table.Both tables must have the same number of columns.In this particular case, there are no duplicate rows, so UNION ALL will produce the same results: SELECT * You'll likely use UNION ALL far more often than UNION. ![]() If you'd like to append all the values from the second table, use UNION ALL. More specifically, when you use UNION, the dataset is appended, and any rows in the appended table that are exactly identical to rows in the first table are dropped. ![]() Note that UNION only appends distinct values. The following query will display all results from the first portion of the query, then all results from the second portion in the same table: SELECT *įROM tutorial.crunchbase_investments_part1įROM tutorial.crunchbase_investments_part2 Let's try it out with the Crunchbase investment data, which has been split into two tables for the purposes of this lesson. Put differently, UNION allows you to write two separate SELECT statements, and to have the results of one statement display in the same table as the results from the other statement. SQL joins allow you to combine two datasets side-by-side, but UNION allows you to stack one dataset on top of the other. Starting here? This lesson is part of a full-length tutorial in using SQL for Data Analysis. ![]()
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