![]() I don't know how long this SQL Fiddle will persist, but here is an example: !15/1d3b4/3. With a table containing 1, 'foo', 2, 'bar', 3, 'baz' this will return records 1 & 2. To use the CASE WHEN result in the WHERE clause you need to wrap it up in a subquery like you did, or in a view. GROUP BY t.id, m.value, y.value, p.city, ht.value ORDER BY t.id LIMIT 100 OFFSET 0 WHERE datetime_sold IS NULL AND datetime_deleted IS NULL AND t.published=true AND coordinates IS NOT NULL AND coordinates & ST_MakeEnvelope(17.831490030182, 44.404640972306, 12.151558389557, 47.837396630872) AND main_image_description IS NOT NULL LEFT JOIN table_houses_types ht on ht.id = t.houses_type_id LEFT JOIN post_codes p ON p.id = t.post_code_id LEFT JOIN table_types y ON y.id = t.type_id ![]() WHEN t.id IN (SELECT rl.table_id FROM table_private_list rl WHERE rl.owner_id=t.user_id AND rl.user_id=41026) THENįROM table t LEFT JOIN table_modes m ON m.id = t.mode_id I am using Postgres 9.4.Įdited: SELECT count(*) OVER() AS count, t.id, t.size, t.price, t.location, t.user_id, p.city, t.price_type, ht.value as houses_type_value, ST_X(t.coordinates) as x, ST_Y(t.coordinates) AS y,ĪRRAY What is the best/fastest way to exclude some rows if result of case statement is null? I need 100 rows (or less if not exists - of course). Probably (I am not sure) I could use LIMIT and OFFSET outside select case statement (where WHERE statement is), but I think (I am not sure why) this would be a performance hit.Ĭase returns array or null. SELECT id, name, case when complex_with_subqueries_and_multiple_when END AS dīut now I am not getting a 100 rows as result. Then I thought I can use it like this: select * from ( SELECT id, name, case when complex_with_subqueries_and_multiple_when END AS d ![]() I would like to use this result in WHERE clause, but Postgres says column 'd' does not exists. Learn more about PostgreSQL in the Xojo Dev Center.I use complex CASE WHEN for selecting values. If you use a tool’s UI to create a table and have a habit of typing in mixed case, the tool might generate SQL (or even the table itself) for you using quotes, which as you can see could mess you up later. Obviously that can start to become a bit of a pain, so the moral of the story is don’t use quotes when creating tables or writing SQL queries so that everything is created as lowercase and things will work like you probably expect. You’ll especially want to pay attention to any tools you use to create SQL for you. To avoid this error you instead have to write the SQL with quotes like this: SELECT "FullName" FROM "Person" This is because PostgreSQL is converting “Person” to “person”, but there is no table called “person”. Now what happens if you try to run a query with a table called “Person”? Well, using SQL like this: SELECT FullName FROM Person This means you’ll get a table called “Person” with two columns called “FullName” and “Address”. In the last example, the names are in quotes so their case is maintained. In the first two examples, you get a table called “person” with two columns called “fullname” and “address”. That may not be obvious in the second example since the names are not lowercase, but remember that PostgreSQL converts your SQL to lowercase for you. For example, consider these SQL CREATE statements: CREATE TABLE person (fullname VARCHAR(100), address VARCHAR(100)) CREATE TABLE Person (FullName VARCHAR(100), Address VARCHAR(100)) CREATE TABLE "Person" ("FullName" VARCHAR(100), "Address" VARCHAR(100)) That is nice if you happen to like to write your queries with mixed casing.īut you’ll start to run into a problem if you’ve actually created the table with case-sensitive names, which happens when you use quotes around the names. ![]() This gets converted to: SELECT fullname FROM person So take a look at this SQL: SELECT FullName FROM Person What it actually does is convert your SQL to lowercase by default. Sometimes you hear that PostgreSQL is case-insensitive, but it isn’t really. I’ve ran into PostgreSQL case sensitivity myself before and I’ve seen it come up on the forums, so I thought it might be a good thing to bring up here. ![]()
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