Question

我正在尝试在Rails中为外键添加索引：

add_index :reports, :unit_id

不幸的是，它给了我以下错误：

==  AddIndexToReportsUnitId: migrating ========================================
-- add_index(:reports, :unit_id)
rake aborted!
An error has occurred, this and all later migrations canceled:

PG::Error: ERROR:  current transaction is aborted, commands ignored until end of transaction block
: 
           SELECT distinct i.relname, d.indisunique, d.indkey, pg_get_indexdef(d.indexrelid), t.oid,
                  m.amname, pg_get_expr(d.indpred, t.oid), pg_get_expr(d.indexprs, t.oid)
           FROM pg_class t
           INNER JOIN pg_index d ON t.oid = d.indrelid
           INNER JOIN pg_class i ON d.indexrelid = i.oid
           INNER JOIN pg_am m ON i.relam = m.oid
           WHERE i.relkind = 'i'
             AND d.indisprimary = 'f'
             AND t.relname = 'reports'
             AND i.relnamespace IN (SELECT oid FROM pg_namespace WHERE nspname = ANY (current_schemas(false)) )
          ORDER BY i.relname

知道为什么会这样吗？它只在我尝试向此特定列添加索引时发生。我能够将索引添加到另一列。

Answer 1

好的，我想我明白为什么会这样。我已经在该列上有一个索引：

${PATH};C:\cygwin\bin

哇，我希望它在提出异常时给了我更好的暗示。

无法将索引添加到外键

1 个答案: