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【DM版本】: 达梦8
【操作系统】：Linux(CentOS 7)
【CPU】:
【问题描述】*：

错误号: -529

错误消息: 超出全局分组空间，请调整 HAGR_BUF_GLOBAL_SIZE HAGR_BUF_SIZE HAGR_BLK_SIZE

SQL脚本如下：

CREATE TABLE "TEST"."ROOM"
(
"ID" BIGINT IDENTITY(1, 1) NOT NULL,
"ROOM_NAME" VARCHAR(255) NOT NULL,
"STATUS" INT DEFAULT 0 NOT NULL,
"ACT_ID" VARCHAR(255),
"PLAN_ID" BIGINT,
"CREATE_TIME" TIMESTAMP(0),
"START_TIME" TIMESTAMP(0),
"TASK_ID" VARCHAR(100),
NOT CLUSTER PRIMARY KEY("ID"),
CONSTRAINT "INDEX_ROOM_ID" UNIQUE("ACT_ID")) STORAGE(ON "MAIN", CLUSTERBTR) ;

CREATE  INDEX "ROOM_PLAN_ID" ON "WARN"."ROOM"("PLAN_ID" ASC) STORAGE(ON "MAIN", CLUSTERBTR) ;
CREATE  INDEX "ROOM_ID" ON "WARN"."ROOM"("ID" ASC) STORAGE(ON "MAIN", CLUSTERBTR) ;
CREATE UNIQUE  INDEX "ACT_ID" ON "WARN"."ROOM"("ACT_ID" ASC) STORAGE(ON "MAIN", CLUSTERBTR) ;

CREATE TABLE "TEST"."ALERT"
(
"ALERT_ID" BIGINT IDENTITY(1, 1) NOT NULL,
"ALERT_TIME" TIMESTAMP(0) NOT NULL,
"ROOM_ID" BIGINT NOT NULL,
"ALERT_TEXT" TEXT,
"USER_ID" VARCHAR(255),
"PROCESS_STATUS" INT DEFAULT 0 NOT NULL,
"PROCESS_TIME" TIMESTAMP(0),
"ALERT_TYPE" VARCHAR(255) NOT NULL,
"MP3_URL" VARCHAR(255),
"KEYWORD" VARCHAR(255),
NOT CLUSTER PRIMARY KEY("ALERT_ID")) STORAGE(ON "MAIN", CLUSTERBTR) ;

CREATE  INDEX "ALERT_ALERT_TYPE" ON "WARN"."ALERT"("ALERT_TYPE" ASC) STORAGE(ON "MAIN", CLUSTERBTR) ;
CREATE  INDEX "ALERT_ROOM_ID" ON "WARN"."ALERT"("ROOM_ID" ASC) STORAGE(ON "MAIN", CLUSTERBTR) ;
CREATE UNIQUE  INDEX "ALERT_ALERT_ID" ON "WARN"."ALERT"("ALERT_ID" ASC) STORAGE(ON "MAIN", CLUSTERBTR) ;

异常SQL如下：

SELECT
	r.id AS id,
	r.room_name AS roomName,
	r.status AS status,
	r.act_id AS actId,
	r.plan_id AS planId,
	COUNT(a.room_id) AS alertNumber
FROM TEST.room r LEFT JOIN TEST.alert a ON r.id = a.room_id
GROUP BY r.id,r.room_name,r.status,r.act_id,r.plan_id,a.room_id
ORDER BY r.id DESC;

执行计划如下：

请问，此条SQL语句如何优化才能不出现这种异常。