我在删除某些行并根据java中的条件更新表时收到以下错误。我的数据库是PostgreSQL 8.4。以下是错误： 错误：重复键值违反唯一 约束“xak1fact_dim_relationship”
解决此问题的代码如下：
/**
* Commits job. This does the following:
* <OL>
* <LI> cancel previous datamart states </LI>
* <LI> drop diabled derived objects </LI>
* <LI> flip mirror relationships for objects with next states </LI>
* <LI> advance rolloff_state from start1 to complete1, from start2 to complete </LI>
* <LI> set 1/0 internal states to 0/-1 </LI>
* <LI> remove header objects with no letter rows </LI>
* <LI> mark mirror rel as OS if children are missing (e.g., semantic w/o agg build) </LI>
* <LI> mark mirror rel as OS if int-map not in sync with dim base (e.g., int-map SQL w/o semantic) </LI>
* </OL>
*/
protected void CommitJobUnprotected()
throws SQLException
{
if (_repl.epiCenterCon== null)
throw makeReplacementError(0);
boolean oldAutoCommitStatus = _repl.epiCenterCon.getAutoCommit();
try
{
_repl.epiCenterCon.setAutoCommit(false);
Statement stmt = null;
boolean committed = false;
synchronized (SqlRepl.metaChangeLock)
{
try
{
stmt = _repl.epiCenterCon.createStatement();
// update internal states for fact_dim_relationship
metaExec(stmt, "DELETE from fact_dim_relationship WHERE internal_state = -1 AND " +
" EXISTS (SELECT 1 FROM fact_dim_relationship WHERE internal_state = 1)",
" SELECT 1 from fact_dim_relationship WHERE internal_state = -1 AND " +
" EXISTS (SELECT 1 FROM fact_dim_relationship WHERE internal_state = 1)"); /*1*/
metaExec( stmt, "UPDATE fact_dim_relationship SET internal_state = internal_state - 1 " +
" WHERE EXISTS (SELECT 1 FROM fact_dim_relationship inner1 " +
" WHERE inner1.internal_state = 1 " +
" AND inner1.fact_tbl_key = fact_dim_relationship.fact_tbl_key " +
" AND inner1.dim_base_key = fact_dim_relationship.dim_base_key ) ",
" SELECT 1 FROM fact_dim_relationship " +
" WHERE EXISTS (SELECT 1 FROM fact_dim_relationship inner1 " +
" WHERE inner1.internal_state = 1 " +
" AND inner1.fact_tbl_key = fact_dim_relationship.fact_tbl_key " +
" AND inner1.dim_base_key = fact_dim_relationship.dim_base_key ) "); /*5*/
System.out.println("Update done on fact_dim_relationship");
_repl.doDrop(SqlReplLogger.DB_META, stmt, "fact_agg", "SELECT fact_agg_key FROM fact_agg f WHERE " +
" NOT EXISTS (SELECT 1 FROM fact_agg_letter l WHERE " +
" f.fact_agg_key = l.fact_agg_key) "); /*6*/
_repl.doDrop(SqlReplLogger.DB_META, stmt, "dim_base_agg", "SELECT dim_base_agg_key FROM dim_base_agg d WHERE " +
" NOT EXISTS (SELECT 1 FROM dim_base_agg_letter l WHERE " +
" d.dim_base_agg_key = l.dim_base_agg_key) "); /*6*/
CheckOutOfSync(stmt, "fact_agg", null); /*7*/
CheckOutOfSync(stmt, "dim_base_agg", null); /*7*/
metaExec( stmt, " update mirror_relationship set relation_to_current = 'Out Of Sync' " +
" where dim_col_intmap_key is not null " +
" and relation_to_current = 'One Back' " +
" and not exists ( " +
" select 1 " +
" from mirror_relationship m2, dim_col_view c, dim_col_intmap i " +
" where m2.dim_base_key = c.dim_base_key " +
" and c.dim_col_key = i.dim_col_key " +
" and i.dim_col_intmap_key = mirror_relationship.dim_col_intmap_key " +
" and m2.relation_to_current = 'One Back') ",
" SELECT 1 FROM mirror_relationship " +
" where dim_col_intmap_key is not null " +
" and relation_to_current = 'One Back' " +
" and not exists ( " +
" select 1 " +
" from mirror_relationship m2, dim_col_view c, dim_col_intmap i " +
" where m2.dim_base_key = c.dim_base_key " +
" and c.dim_col_key = i.dim_col_key " +
" and i.dim_col_intmap_key = mirror_relationship.dim_col_intmap_key " +
" and m2.relation_to_current = 'One Back') "); /*8*/
// clean out the tables used by mombuilder, aggbuilder, and semantics
metaExec( stmt, "delete from relation_intermediary", "select 1 from relation_intermediary" );
_repl.epiCenterCon.commit();
committed = true;
}
finally
{
safeMetaRollbackIfNeeded( committed );
_repl.safeClose( null, stmt );
}
} // end synchronized block
}
finally
{
_repl.epiCenterCon.setAutoCommit(oldAutoCommitStatus);
}
}
第一个删除语句运行良好，但在运行更新时会抛出上述异常....！我们支持SQLServer，Oracle和DB2，并且相同的代码可以与其他DB一起运行。顺便说一下，我们在READ_COMMITTED事务级别运行这些语句，如果在安全回滚之间发生任何故障，我们将关闭自动提交。如果我用autocommit运行上面的代码，则代码工作正常！但我们不应该这样做。我怀疑PostgreSQL的Multi版本并发控制功能，我错误地设置了隔离级别吗？请尽早帮助我。我可以提供你想要的任何信息。
答案 0 :(得分：1)
如果只是这一组特定查询，请使用SET CONSTRAINT：
BEGIN;
SET CONSTRAINT = xak1fact_dim_relationship DEFERRED;
-- Do your SQL
COMMIT;
如果这是一种非常常见的情况，您可以更改数据库架构，更改数据库架构以支持INITIALLY DEFERRED。