Skip to main content

Fixing Hanging Hive DROP TABLE on PostgreSQL Metastore

By Anonymous
Struggling with delivery, architecture alignment, or platform stability?

I help teams fix systemic engineering issues: processes, architecture, and clarity.
→ See how I work with teams.


On some older Hive deployments with PostgreSQL as the metastore database, DROP TABLE can hang while PostgreSQL shows UPDATE locks on metastore tables. This often happens when certain privilege tables and indexes were not created correctly during an upgrade or manual schema setup. This note shows a legacy DDL patch you can apply to add the missing tables and indexes so DROP TABLE completes successfully again. Always back up your metastore before running any DDL.

Important legacy note: The SQL below matches a specific generation of the Hive metastore schema from around 2013. You should only apply it if you have confirmed that these tables and indexes are missing in your metastore and that the definitions match your Hive version. Always test on a non-production copy of your metastore first.

Symptom

When using PostgreSQL as the Hive metastore database, a statement like: 

DROP TABLE xyz;

may hang indefinitely. On the PostgreSQL side, you see long-running transactions and locks with UPDATE operations on metastore tables, even though no obvious workload is active.

This can be caused by missing indexes and privilege tables that Hive expects to exist. Without them, metadata operations (including DROP TABLE) can block or fail.

DDL patch for missing Hive metastore tables and indexes (PostgreSQL)

The following SQL creates the missing indexes on IDXS and the privilege/role-related tables and indexes. Run it against your metastore database from the psql CLI, connected as the Hive metastore user. 

-- Indexes on IDXS
CREATE INDEX "IDXS_FK1" ON "IDXS" USING btree ("SD_ID");
CREATE INDEX "IDXS_FK2" ON "IDXS" USING btree ("INDEX_TBL_ID");
CREATE INDEX "IDXS_FK3" ON "IDXS" USING btree ("ORIG_TBL_ID");

-- ROLES table
CREATE TABLE "ROLES" (
  "ROLE_ID"      bigint      NOT NULL,
  "CREATE_TIME"  int         NOT NULL,
  "OWNER_NAME"   varchar(128) DEFAULT NULL,
  "ROLE_NAME"    varchar(128) DEFAULT NULL,
  PRIMARY KEY ("ROLE_ID"),
  CONSTRAINT "ROLEENTITYINDEX" UNIQUE ("ROLE_NAME")
);

-- ROLE_MAP table
CREATE TABLE "ROLE_MAP" (
  "ROLE_GRANT_ID" bigint      NOT NULL,
  "ADD_TIME"      int         NOT NULL,
  "GRANT_OPTION"  smallint    NOT NULL,
  "GRANTOR"       varchar(128) DEFAULT NULL,
  "GRANTOR_TYPE"  varchar(128) DEFAULT NULL,
  "PRINCIPAL_NAME" varchar(128) DEFAULT NULL,
  "PRINCIPAL_TYPE" varchar(128) DEFAULT NULL,
  "ROLE_ID"        bigint      DEFAULT NULL,
  PRIMARY KEY ("ROLE_GRANT_ID"),
  CONSTRAINT "USERROLEMAPINDEX"
    UNIQUE ("PRINCIPAL_NAME","ROLE_ID","GRANTOR","GRANTOR_TYPE"),
  CONSTRAINT "ROLE_MAP_FK1"
    FOREIGN KEY ("ROLE_ID") REFERENCES "ROLES" ("ROLE_ID")
);

-- GLOBAL_PRIVS table
CREATE TABLE "GLOBAL_PRIVS" (
  "USER_GRANT_ID"   bigint      NOT NULL,
  "CREATE_TIME"     int         NOT NULL,
  "GRANT_OPTION"    smallint    NOT NULL,
  "GRANTOR"         varchar(128) DEFAULT NULL,
  "GRANTOR_TYPE"    varchar(128) DEFAULT NULL,
  "PRINCIPAL_NAME"  varchar(128) DEFAULT NULL,
  "PRINCIPAL_TYPE"  varchar(128) DEFAULT NULL,
  "USER_PRIV"       varchar(128) DEFAULT NULL,
  PRIMARY KEY ("USER_GRANT_ID"),
  CONSTRAINT "GLOBALPRIVILEGEINDEX"
    UNIQUE ("PRINCIPAL_NAME","PRINCIPAL_TYPE","USER_PRIV","GRANTOR","GRANTOR_TYPE")
);

-- DB_PRIVS table
CREATE TABLE "DB_PRIVS" (
  "DB_GRANT_ID"    bigint      NOT NULL,
  "CREATE_TIME"    int         NOT NULL,
  "DB_ID"          bigint      DEFAULT NULL,
  "GRANT_OPTION"   smallint    NOT NULL,
  "GRANTOR"        varchar(128) DEFAULT NULL,
  "GRANTOR_TYPE"   varchar(128) DEFAULT NULL,
  "PRINCIPAL_NAME" varchar(128) DEFAULT NULL,
  "PRINCIPAL_TYPE" varchar(128) DEFAULT NULL,
  "DB_PRIV"        varchar(128) DEFAULT NULL,
  PRIMARY KEY ("DB_GRANT_ID"),
  CONSTRAINT "DBPRIVILEGEINDEX"
    UNIQUE ("DB_ID","PRINCIPAL_NAME","PRINCIPAL_TYPE",
            "DB_PRIV","GRANTOR","GRANTOR_TYPE"),
  CONSTRAINT "DB_PRIVS_FK1"
    FOREIGN KEY ("DB_ID") REFERENCES "DBS" ("DB_ID")
);

-- PART_PRIVS table
CREATE TABLE "PART_PRIVS" (
  "PART_GRANT_ID"  bigint      NOT NULL,
  "CREATE_TIME"    int         NOT NULL,
  "GRANT_OPTION"   smallint    NOT NULL,
  "GRANTOR"        varchar(128) DEFAULT NULL,
  "GRANTOR_TYPE"   varchar(128) DEFAULT NULL,
  "PART_ID"        bigint      DEFAULT NULL,
  "PRINCIPAL_NAME" varchar(128) DEFAULT NULL,
  "PRINCIPAL_TYPE" varchar(128) DEFAULT NULL,
  "PART_PRIV"      varchar(128) DEFAULT NULL,
  PRIMARY KEY ("PART_GRANT_ID"),
  CONSTRAINT "PART_PRIVS_FK1"
    FOREIGN KEY ("PART_ID") REFERENCES "PARTITIONS" ("PART_ID")
);

CREATE INDEX "PARTPRIVILEGEINDEX"
  ON "PART_PRIVS"
  USING btree ("PART_ID","PRINCIPAL_NAME","PRINCIPAL_TYPE",
               "PART_PRIV","GRANTOR","GRANTOR_TYPE");

-- PART_COL_PRIVS table
CREATE TABLE "PART_COL_PRIVS" (
  "PART_COLUMN_GRANT_ID" bigint      NOT NULL,
  "COLUMN_NAME"          varchar(128) DEFAULT NULL,
  "CREATE_TIME"          int          NOT NULL,
  "GRANT_OPTION"         smallint     NOT NULL,
  "GRANTOR"              varchar(128) DEFAULT NULL,
  "GRANTOR_TYPE"         varchar(128) DEFAULT NULL,
  "PART_ID"              bigint       DEFAULT NULL,
  "PRINCIPAL_NAME"       varchar(128) DEFAULT NULL,
  "PRINCIPAL_TYPE"       varchar(128) DEFAULT NULL,
  "PART_COL_PRIV"        varchar(128) DEFAULT NULL,
  PRIMARY KEY ("PART_COLUMN_GRANT_ID"),
  CONSTRAINT "PART_COL_PRIVS_FK1"
    FOREIGN KEY ("PART_ID") REFERENCES "PARTITIONS" ("PART_ID")
);

CREATE INDEX "PARTITIONCOLUMNPRIVILEGEINDEX"
  ON "PART_COL_PRIVS"
  USING btree ("PART_ID","COLUMN_NAME","PRINCIPAL_NAME","PRINCIPAL_TYPE",
               "PART_COL_PRIV","GRANTOR","GRANTOR_TYPE");

How to apply this in PostgreSQL

Connect to your Hive metastore database with psql and paste the DDL: 

psql -h <HOSTNAME> -d metastore -U hiveuser -W

After the tables and indexes have been created successfully, retry: 

DROP TABLE xyz;

In many legacy setups this resolves the hanging DROP TABLE issue because the metastore schema now matches what Hive expects and PostgreSQL can evaluate privilege and metadata queries efficiently instead of stalling on missing objects.

Reminder: Always dump and back up your metastore before running manual DDL like this, and validate that your Hive version expects these exact table and column names.

Related guides:

If you need help with distributed systems, backend engineering, or data platforms, check my Services.

Labels:

Most read articles

Building a Model-Agnostic Multi-Agent System with OpenClaw

By
Over one week we rebuilt our AI stack around OpenClaw’s multi-agent architecture to avoid provider lock-in and stop wasting premium tokens. By aligning models to tasks, diversifying fallbacks across providers, enforcing minimal tool access, and switching to memory-first workflows with ephemeral sessions, we reduced token usage per task by about 70% and cut our monthly bill by 77% while improving operational resilience. How We Achieved 77% Cost Reduction and Provider Independence Over the past week, we rebuilt our AI infrastructure around OpenClaw’s multi-agent architecture. The result was a 77% cost reduction , provider independence , and a delegation system that routes work to the most cost-effective model for each job. Below is the technical journey of optimizing a 7-agent squad with OpenClaw. The Challenge: Model Provider Lock-In We started with a simple problem: our entire squad defaulted to a single model provider. This created three issues: Cost inefficiency beca...
Read more

BacNet => MQTT in Production: The Real Cost of Bridging BACnet to MQTT at Scale

By
bacnet2mqtt looks simple in a README and expensive in production. Once BACnet polling, reconnection behavior, stale state, and MQTT publishing collide, teams discover they are not deploying a lightweight adapter but operating infrastructure. This article breaks down where bacnet2mqtt works, where it becomes a bottleneck, and which production patterns reduce the operational damage before incidents, backlogs, and silent data loss turn a building integration into a long-running engineering problem. I inherited a building controls integration problem 18 months ago. Three office floors. 217 BACnet sensors covering temperature, occupancy, and HVAC actuators. The data was trapped inside the building automation network while the business wanted analytics, reporting, and compliance visibility in the data platform. The obvious answer looked easy enough: deploy bacnet2mqtt, bridge BACnet into MQTT, and push the stream into the lakehouse stack. The repository made it sound like a w...
Read more

Get Apache Flume 1.3.x running on Windows

By Anonymous
Since we found an increasing interest in the flume community to get Apache Flume running on Windows systems again, I spent some time to figure out how we can reach that. Finally, the good news - Apache Flume runs on Windows. You need some tweaks to get them running. Prerequisites Build system: maven 3x, git, jdk1.6.x, WinRAR (or similar program) Apache Flume agent: jdk1.6.x, WinRAR (or similar program), Ultraedit++ or similar texteditor Tweak the Windows build box 1. Download and install JDK 1.6x from Oracle 2. Set the environment variables    => Start - type " env " into the search box, select " E dit system environment variables ", click Environment Variables, Select " New " from the " Systems variables " box, type " JAVA_HOME " into " variable name " and the path to your JDK installation into "Variable value" (Example:  C:\Program Files (x86)\Java\jdk1.6.0_33 ) 3. Download maven from Apache 4. Set...
Read more