> On 30 Jan 2020, at 21:12, Keith Medcalf <kmedc...@dessus.com> wrote: > > On Thursday, 30 January, 2020 12:20, Simon Slavin <slav...@bigfraud.org> > wrote: > >> I would appreciate your help. Reading a technical article today, I came >> across a casual reference to "Standard SQL" as if it was a well-known >> thing. This worried me since I've never heard the term and I'm meant to >> know about such things.
I’m an author using that term. What I personally mean with “Standard SQL” is the language described by ISO/IEC 9075. (Sorry, I’m saying ISO/IEC 9075 a lot in my response to avoid the term “standard” and the related confusion). > > I would say that "Standard SQL" is that variant of SQL is that "minimal > common subset" dialect of SQL that is understood by every single > implementation claiming to be "SQL compliant" that has ever existed until the > present. In other words, it is the dialect of SQL that will be understood by > *any* software claiming to be "SQL compliant". I think the word for what you describe is “Core SQL”. I wrote about it here: https://modern-sql.com/standard/levels > >> It doesn't seem to refer to the official standard for SQL, which is huge >> and contains a plethora of features implemented once or never. The >> author seemed to think it was a sort of 'core SQL' – features identically >> implemented by all, or most, of the well-known SQL engines. Google, for example, is also using the term “Standard SQL” for products like BigQuery. Although Googles “Standard SQL” is more close to ISO/IEC 9075 that the other “SQL” dialects they offer, they are sill not conforming to ISO/IEC 9075 in pretty basic ways. > > There is a core SQL. It is not defined. It is defined in ISO/IEC 9075. There are tables called (quoting): “Feature taxonomy and definition for mandatory features”, contains a taxonomy of the features of SQL language in Core SQL that are specified in this part of ISO/IEC 9075. There is an explicit list of mandatory features for Core SQL. And there are many optional features. > Most SQL (particularly DDL) is "implementation specific". About the only > things that comprise "standard SQL" are the DML constructs: ISO/IEC 9075 also defines DDL. Generally ISO/IEC 9075 only describes semantics, but no implementation details. E.g. CREATE TABLE is defined, CREATE INDEX not. ISO/IEC 9075 allows language extensions as long as they use a syntax **not** described in ISO/IEC 9075. > > INSERT INTO <table> (<column list>) VALUES (<value list>); > SELECT <column list> FROM <table list> [WHERE <condition>] [GROUP BY <column > list> [HAVING <having list>]] [ORDER BY <ordering list>] > DELETE FROM <table> [WHERE <condition>] > UPDATE <table> SET <column> = <value>[, <column> = <value>]... [WHERE > <condition>] > >> The one possibility I can think of is SQL:1999. This is the first >> version which has features marked as 'mandatory' or 'optional'. A full >> implementation of all mandatory features could, I suppose, be called >> "Standard SQL", but I've never heard of that term being used for that. > > This is very Johnny-lately. I think the first standard was SQL-85 but even > that was chock full of vendor implementation specifics and light on being > "standard". Subsequent versions of the SQL Standard committee output simply > became more a practice in documenting vendor implementation specifics rather > than defining a standard. Most standards suffer from this problem. > >> Have any of you been using this term for a meaning other than "Fully >> conforming to SQL:2019 (or whatever version you think current) ? Do you >> have documentation somewhere ? Or are my suspicions correct and there's >> no such thing ? > > Yes. "standard SQL" is that subset of SQL that is understood by every > implemetation ever without making changes. Well, that’s now how I’m using this term. Not does Google use it in this way. -markus _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
