What if I wrote a very long, complicated query that I'd like to test against different tables (like test tables), and let's say I can't use stored functions or procedures. How could I pass different tables to my query?
CREATE TABLE data_a AS (SELECT 'a' AS test_case, 1 AS value);
CREATE TABLE data_b AS (SELECT 'b' AS test_case, 2 AS value);
CREATE VIEW data AS (SELECT * FROM data_a UNION ALL SELECT * FROM data_b);
CREATE VIEW complicated_query AS (SELECT test_case, value+1 FROM data);
SELECT * FROM complicated_query WHERE test_case = 'a';
SELECT * FROM complicated_query WHERE test_case = 'b'; CREATE TABLE data_a AS (SELECT 'a' AS test_case, 1 AS value);
CREATE TABLE data_b AS (SELECT 'b' AS test_case, 2 AS value);
CREATE TABLE data_prod AS (SELECT NULL AS test_case, prod_table.value FROM prod_table);
CREATE VIEW data AS (SELECT * FROM data_a UNION ALL SELECT * FROM data_b UNION ALL SELECT * FROM data_prod);
CREATE VIEW complicated_query AS (SELECT test_case, value+1 FROM data);
-- when testing
SELECT * FROM complicated_query WHERE test_case = 'a';
SELECT * FROM complicated_query WHERE test_case = 'b';
-- when in 'production'
SELECT * FROM complicated_query WHERE test_case IS NULL;This perfectly illustrates my point. You had to manually defunctionalize your data model and queries to support what I'm saying should be inherently part of SQL.
1) Only if you define Pascal as only Wirth's very first version. That changed almost immediately.
2) Only if you refuse to equate “pointer to function” with “function”. Which in C, where “everything is a pointer” (a bit like in Unix Linux “everything is a file”), seems rather silly.