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https://issues.apache.org/jira/browse/CASSANDRA-2025?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12986448#action_12986448
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Eric Evans commented on CASSANDRA-2025:
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bq. I think float literals in property names is just bad form.
Float literals in property names would be, yes. :) But a float
comparator/validator, and hence column names/values, specified in CQL
statements using float literals, seems entirely possible.
Assuming the same syntax used to describe structures here (dot delim) was used
where the members were column names and or values, (compound column names was
the example that came to my mind), then it would need to be something that
could be unambiguously parsed.
> generalized way of expressing hierarchical values
> -------------------------------------------------
>
> Key: CASSANDRA-2025
> URL: https://issues.apache.org/jira/browse/CASSANDRA-2025
> Project: Cassandra
> Issue Type: Sub-task
> Components: API
> Reporter: Eric Evans
> Assignee: Eric Evans
> Priority: Minor
> Fix For: 0.8
>
> Original Estimate: 0h
> Remaining Estimate: 0h
>
> While hashing out {{CREATE KEYSPACE}}, it became obvious that we needed a
> syntax for expressing hierarchical values. Properties like
> {{replication_factor}} can be expressed simply using keyword arguments like
> ({{replication_factor = 3}}), but {{strategy_options}} is a map of strings.
> The solution I took in CASSANDRA-1709 was to dot-delimit "map name" and
> option key, so for example:
> {code:style=SQL}
> CREATE KEYSPACE keyspace WITH ... AND strategy_options.DC1 = "1" ...
> {code}
> This led me to wonder if this was a general enough approach for any future
> cases that might come up. One example might be compound/composite column
> names. Dot-delimiting is a bad choice here since it rules out ever
> introducing a float literal.
> One suggestion would be to colon-delimit, so for example:
> {code:style=SQL}
> CREATE KEYSPACE keyspace WITH ... AND strategy_options:DC1 = "1" ...
> {code}
> Or in the case of composite column names:
> {code:style=SQL}
> SELECT columnA:columnB,column1:column2 FROM Standard2 USING
> CONSISTENCY.QUORUM WHERE KEY = key;
> UPDATE Standard2 SET columnA:columnB = valueC, column1:column2 = value3 WHERE
> KEY = key;
> {code}
> As an aside, this also led me to the conclusion that {{CONSISTENCY.<LEVEL>}}
> is probably a bad choice for consistency level specification. It mirrors the
> underlying enum for no good reason and should probably be changed to
> {{CONSISTENCY <LEVEL>}} (i.e. omitting the separator). For example:
> {code:style=SQL}
> SELECT column FROM Standard2 USING CONSISTENCY QUORUM WHERE KEY = key;
> {code}
> Thoughts?
> *Edit: improved final example*
> *Edit: restore final example, create new one (gah).*
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