• B
    Attached is a patch for JDBC's getColumn() function that was broken / · 57040f78
    Bruce Momjian 提交于
    flawed in the following ways:
    
    1. Only returned columns that had a default value defined, rather than all
    columns in a table
    2. Used 2 * N + 1 queries to find out attributes, comments and typenames
    for N columns.
    
    By using some outer join syntax it is possible to retrieve all necessary
    information in just one SQL statement. This means this version is only
    suitable for PostgreSQL >= 7.1. Don't know whether that's a problem.
    
    I've tested this function with current sources and 7.1.3 and patched both
    jdbc1 and jdbc2. I haven't compiled nor tested the jdbc1 version though, as
    I have no JDK 1.1 available.
    
    Note the discussion in http://fts.postgresql.org/db/mw/msg.html?mid=1029626
    regarding differences in obtaining comments on database object in 7.1 and
    7.2. I was unable to use the following syntax (or similar ones):
    
    select
         ...,
         description
    from
         ...
         left outer join col_description(a.attrelid, a.attnum) description
    order by
         c.relname, a.attnum;
    
    (the error was parse error at or near '(') so I had to paste the actual
    code for the col_description function into the left outer join. Maybe
    someone who is more knowledgable about outer joins might provide me with a
    better SQL statement.
    
    Jeroen van Vianen
    57040f78
DatabaseMetaData.java 94.6 KB