ERROR: cannot execute INSERT in a read-only transaction

• 场景：PostgreSQL 集群执行 insert 语句时，报如下错误：

SQL 错误 [25006]: ERROR: cannot execute INSERT in a read-only transaction

错误位置:

org.jkiss.dbeaver.model.sql.DBSQLException: SQL 错误 [25006]: ERROR: cannot execute INSERT in a read-only transaction
	at org.jkiss.dbeaver.model.impl.jdbc.exec.JDBCStatementImpl.executeStatement(JDBCStatementImpl.java:133)
	at org.jkiss.dbeaver.ui.editors.sql.execute.SQLQueryJob.executeStatement(SQLQueryJob.java:582)
	at org.jkiss.dbeaver.ui.editors.sql.execute.SQLQueryJob.lambda$1(SQLQueryJob.java:491)
	at org.jkiss.dbeaver.ui.editors.sql.execute.SQLQueryJob.executeSingleQuery(SQLQueryJob.java:501)
	at org.jkiss.dbeaver.ui.editors.sql.execute.SQLQueryJob.extractData(SQLQueryJob.java:934)
	at org.jkiss.dbeaver.ui.editors.sql.SQLEditor$QueryResultsContainer.readData(SQLEditor.java:3935)
	at org.jkiss.dbeaver.ui.controls.resultset.ResultSetJobDataRead.lambda$0(ResultSetJobDataRead.java:123)
	at org.jkiss.dbeaver.model.exec.DBExecUtils.tryExecuteRecover(DBExecUtils.java:190)
	at org.jkiss.dbeaver.ui.controls.resultset.ResultSetJobDataRead.run(ResultSetJobDataRead.java:121)
	at org.jkiss.dbeaver.ui.controls.resultset.ResultSetViewer$ResultSetDataPumpJob.run(ResultSetViewer.java:5147)
	at org.jkiss.dbeaver.model.runtime.AbstractJob.run(AbstractJob.java:105)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)
Caused by: org.postgresql.util.PSQLException: ERROR: cannot execute INSERT in a read-only transaction
	at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2676)
	at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2366)
	at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:356)
	at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:496)
	at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:413)
	at org.postgresql.jdbc.PgStatement.executeWithFlags(PgStatement.java:333)
	at org.postgresql.jdbc.PgStatement.executeCachedSql(PgStatement.java:319)
	at org.postgresql.jdbc.PgStatement.executeWithFlags(PgStatement.java:295)
	at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:290)
	at org.jkiss.dbeaver.model.impl.jdbc.exec.JDBCStatementImpl.execute(JDBCStatementImpl.java:330)
	at org.jkiss.dbeaver.model.impl.jdbc.exec.JDBCStatementImpl.executeStatement(JDBCStatementImpl.java:131)
	... 11 more

• 原因：连接到了集群中的备节点（只读节点），而不是主节点（可写节点）
• 由于我使用 DBeaver 连接时的地址写的是集群

• 需要把连接地址改成主节点的地址，（如果不知道哪个是主节点，就分别去连接，再执行下 insert 语句，能执行成功的就是主节点）

PostgreSQL集群中从节点（standby）天生就是只读的！