![]() Learn more about PostgreSQL in the Xojo Dev Center. 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 postgresql - CASE with max () - Database Administrators Stack Exchange CASE with max () Ask Question Asked 7 years, 1 month ago Modified 7 years, 1 month ago Viewed 15k times 0 I know how to do this in SQL Server but Postgres is different. 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 The conditions here, i.e., condition1, condition2, etc, should be boolean expressions, and hence their evaluation should only return a TRUE or FALSE value. So take a look at this SQL: SELECT FullName FROM Person The syntax for the Postgres Case statement is as follows: CASE WHEN condition1 THEN result1 WHEN condition2 THEN result2 WHEN. 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. How can I compare the description of tableA or tableB against the master_table in a CASE statement? When attempting the above, I am getting an error column schema_z.master_table.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. Usually table schema_z.table1 has the record for specific filters, but others the value has to be extracted from one of the other tables (schema_a.tableA, schema_b.tableB) that are a match for the master_Table in the description. The other tables are using either the code or description of the catalog table. Where schema_z.master_table is the table saving the codes and description catalog. Aprendemos a cómo usar el condicional CASE en un Select para crear una columna donde lo que diga dependa de lo que viene en otra columna. WHEN schema_a.scription = schema_z.master_scription or schema_b.scription = schema_z.master_scription THEN schema_z.master_de::character varying Is there a way to not hard code the description and code in the case statement, and be able to do something like this? CASE Case case checks if a value matches a list of conditions, and returns some output based on the first condition thats met. WHEN 'Admin'::text THEN 'ADM'::character varyingĮLSE COALESCE(schema_a.scription, schema_b.scription) WHEN 'Social Worker'::text THEN 'SW'::character varying (Id rather not use start as column name as thats a keyword in standard SQL - even if allowed in Postgres. ![]() WHEN schema_z.table1.type_code IS NULL THENĬASE COALESCE(schema_a.scription, schema_b.scription) ![]() Currently I have to do something like this to get a correct result: CASE I'd like to use field values instead of hard coded values. Wondering if CASE WHEN in postgres can go beyond these kind of examples: SELECT title, ![]()
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