On Tue, Sep 12, 2017 at 2:17 PM, Mats Wichmann <m...@wichmann.us> wrote: > On 09/12/2017 01:05 PM, boB Stepp wrote: >> As I continue to read about SQL, one thing jumps out: There are many >> differences between how SQL statements are implemented among the >> different database products. Even for relatively simple, >> straightforward things like field concatenation. One DB might use >> "||" as the operator. Another uses "+". Yet another only uses a >> "CONCAT" function. This is crazy!
[...] > But dealing with "local extension to SQL" is a different problem. SQL > is actually a standard and should work the same everywhere, but then > people decide they need to improve it. Being agnostic means avoiding > mysql-specific syntax, postgres-specific syntax, etc. Which means you > need to know what is specific in the first place... In the example I was alluding to, concatenating fields, surely this is a "standard SQL" query? So, for instance, if I had a Sales table with FirstName and LastName fields and wanted to use SQL to get the full name from these: 1) In Microsoft SQL Server: SELECT FirstName + ' ' + LastName FROM Sales 2) MySQL: SELECT CONCAT(FirstName, ' ', LastName) FROM Sales; 3)SQLite: SELECT FirstName || ' ' || LastName FROM Sales; And these would be the SQL commands/statements I would have cursor.execute use from the sqlite3 module. They would be different depending on which database product I was using. Am I horribly misunderstanding something??? And if not, I have several other apparently fundamental SQL examples where similar situations exist based on the book on SQL I am only 43 pages into! -- boB _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
