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Displaying posts with tag: Standard SQL (reset)
Temporary tables, standard SQL

The PostgreSQL manual says:

"The standard's definition of the behavior of temporary tables is widely ignored. PostgreSQL's behavior on this point is similar to that of several other SQL databases."

The first sentence is false. The second sentence could be rephrased as "MySQL copied us", although nobody else did, as far as I know.

The standard's definition is widely followed

I base this claim on the documentation of DB2, Oracle Rdb, Oracle 12c, and …

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The BINARY and VARBINARY data types

MySQL's support of the BINARY and VARBINARY data type is good, and the BINARY and VARBINARY data types are good things. And now the details. What applies here for MySQL applies for MariaDB as well.

Who supports VARBINARY

There's an SQL:2008 standard optional feature T021 "BINARY and VARBINARY data types". Our book has a bigger description, but here is one that is more up to date:

DBMS Standard-ish? Maximum length
DB2 for LUW No. Try CHAR FOR BIT DATA. 254 for fixed-length, 32672 for variable-length
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MySQL versus Firebird

Firebird is an open-source DBMS with a long history and good SQL support. Although I measured Firebird's importance as smaller than MySQL's or MariaDB's, it exists, and might grow a bit when Firebird becomes the default LibreOffice DBMS.

I decided to compare the current versions of MySQL 5.6 and Firebird SQL 2.5. I only looked at features that end users can see, without benchmarking. Preparing for the comparison was easy. I looked at the instructions for downloading Firebird with Ubuntu and within 15 …

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Tuples

"It is better to keep silence and be thought a fool, than to say 'tuple' and remove all doubt."

But recently people have been using the word "tuple" more frequently. Doubtless all those people know that in relational databases a tuple (or a tuple value) is a formal term for a row of a table. It's possible to know a bit more than that.

Pronounced Tyoople, Toople, or Tuhple?

The Oxford Dictionaries site says Tyoople. Other dictionaries are neutral about the terms from which Tuple was derived (sextuple, octuple, etc.), for example Merriam-Webster says they usually end in Toople but Tuhple is an accepted alternate, and the Oxford Canadian Dictionary says …

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Sometimes MySQL is more standards-compliant than PostgreSQL

Here are examples comparing MySQL 5.6 against PostgreSQL 9.3 Core Distribution, where MySQL seems to comply with "standard SQL" more closely than PostgreSQL does. The examples are also true for MariaDB 10.0 so whenever I say "MySQL" I mean "MySQL and/or MariaDB". When I say "more closely" I do not mean that MySQL is completely compliant, or that PostgreSQL is completely non-compliant.

Identifiers

Example:

CREATE TABLE          ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ (s1 INT); /* 32-character name */
SELECT COUNT(*) FROM information_schema.tables
  WHERE table_name = 'ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ';
SELECT COUNT(*) FROM information_schema.tables
  WHERE table_name LIKE LOWER('Ž%');

Result:
PostgreSQL says count(*) is 0. MySQL says it's 1.
Reason:
(1) PostgreSQL maximum identifier length is 63 bytes; MySQL maximum identifier length is 64 …

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How to pronounce SQL

In the thirty-second minute of a YouTube video featuring Oracle CEO Larry Ellison you can hear him say clearly "we compete against Microsoft SQL Server ... we never compete against MySQL".

The important thing is that he says "Microsoft SEQUEL Server" the way Microsoft people say it, but he says "My-ESS-CUE-ELL" the way the MySQL Reference Manual says is "official" pronunciation (for English). That is, for product names Mr Ellison respects the way the product makers say it. That settles that, but what about the word SQL in general?

Although SEQUEL was the earlier name, there are no English words where the letter Q alone is pronounced KW. So this can't be …

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