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Comment by kevin_thibedeau | Hacker News Reader

It was designed to be a DB for Tcl at a time when that language didn't have typed objects. Its SQL implementation reflects that. Where are the grand Python, or Perl, or JS DBs?

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It actually does have typed values, it is just the schema didn’t constrain the value types stored in each column, until relatively recently the column type was mostly just documentation. However, now it has STRICT tables which do constrain the value types of columns. And for a lot longer you’ve been able to implement the same thing manually using check constraints-which is a bit verbose if you are writing the schema by hand, much less of a problem if it is being generated out of ORM model classes/etc

>> It was designed to be a DB for Tcl at a time when that language didn't have typed objects. Its SQL implementation reflects that.

> It actually does have typed values

Now. As the article points out, they were not part of the initial design, because of the Tcl heritage.

AFAIK it has always had typed values. Don’t confuse column types (which constrain a column to containing only values of a specified type) with value types (which enable it to treat the string “12” and the integer 12 and the floating point 12.0 as three distinct values)

Tcl has value types. Tcl 7.x and earlier only had one data type, the string-so adding two integers required two string-to-int conversions followed by an int-to-string conversion. In 1997, Tcl 8.x was released, which internally has distinct values types (int, string, etc), although it retains the outward appearance of “everything-is-a-string” for backward compatibility. So SQLite’s Tcl heritage included distinguishing different types of values, as is done in post-1997 Tcl.

Tcl still only has one data type, which is the string. It has different internal representations to allow representing integers etc more efficiently, but since that is not part of the formal semantics of the language, those representations are not data types.

At the level of its C API-which is the level at which it integrates with sqlite-it indeed has multiple data types, it even has a structure to represent them, Tcl_ObjType: https://www.tcl-lang.org/man/tcl8.4/TclLib/ObjectType.htm

I've never used it, but perl contains support for Berkeley DB in stdlib since forever. But sqlite maps to perl just fine.

ZODB https://zodb.org/en/latest/

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