In JDBC, why do parameter indexes for prepared statements begin at 1 instead of 0?

Question

Everywhere else in Java, anything with an index starts at 0. Is there a reason for the change here or is this just bad design?

I was wondering the same thing, especially since ResultSets are also 1-indexed. — Uri, Apr 03 '10 at 20:24

score 43 · Accepted Answer · answered Mar 05 '09 at 19:04

43

Historically, databases have used 1-based indexing for bound parameters. This probably reflects the origins of relational databases in set theory and mathematics, which index elements starting with one, and use zero to represent a null or empty set.

In shell scripts and regular expressions, the zero index usually means something "special". For example, in the case of shell scripts, the zeroth "argument" is actually the command that was invoked.

The choice for JDBC was deliberate but, ultimately, probably causes more confusion and difficulty than it solves.

answered Mar 05 '09 at 19:04

erickson

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In mathematics it's usually easier to go with zero-indexing (in my experience (third class BSc)). – Tom Hawtin - tackline Mar 05 '09 at 19:18
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I don't think zero-based indexing is a mathematical artifact. Every linear algebra book I have starts numbering rows/columns with 1. FORTRAN defaults from 1, if I recall correctly. I think zero-based indexing is a legacy from C and pointer arithmetic. – duffymo Mar 05 '09 at 20:24
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Personally, I think 0-based indexing is a throwback from C pointer arithmetic which seems to have stuck... to the misfortune of us all. – Lawrence Dol Mar 06 '09 at 06:32
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The beauty of using 0-based indexing is: You can use the interval containing consecutive `N` elements as `[0, N)` and `[N, 2N)`, `[2N, 3N)` and so on so forth. So all mainstream languages like C, C++, Java, JavaScript, Python use the 0-based index convention originally used in C programming language. This principle also applies to generic index like `[a, b)` where `a` is inclusive and `b` is exclusive. – tonga Dec 06 '13 at 02:47

score 21 · Answer 2 · answered Mar 05 '09 at 19:23

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This was part of a plot by the original language designers to weed out the weak. In the original spec, arrays were numbered from -1, and lists with 1 element returned length =0.

Today, only the java Calendar API remains from this diabolical plot.

answered Mar 05 '09 at 19:23

Steve B.

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score 2 · Answer 3 · answered Mar 05 '09 at 19:04

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Personally I would chalk this up to bad design.

answered Mar 05 '09 at 19:04

matt b

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score 2 · Answer 4 · answered Mar 05 '09 at 19:20

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I understand both JDBC and ODBC are based upon the X/Open Call Level Interface. So, it's pre-Java history, like 0-based month numbers.

answered Mar 05 '09 at 19:20

Tom Hawtin - tackline

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score 0 · Answer 5 · answered Mar 05 '09 at 19:02

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Likely it's that JDBC was modeled on ODBC.

answered Mar 05 '09 at 19:02

Dave Costa

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I think both were modeled on an X/Open interface. – Tom Hawtin - tackline Mar 05 '09 at 19:21

score 0 · Answer 6 · answered Mar 05 '09 at 19:03

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More human friendly maybe? Also, Java's regular expression Matcher's group starts with 1 as the first matched group.

answered Mar 05 '09 at 19:03

Steve Kuo

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This is standard with regular expressions as 0 is used to mean the entire match. – Eclipse Mar 05 '09 at 19:06

In JDBC, why do parameter indexes for prepared statements begin at 1 instead of 0?

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