❓ PostgreSQL Insert Appears Stuck — No Error, Just Hanging / Deadlocking

Hi all,

I'm dealing with a persistent issue when trying to insert rows into my new PostgreSQL table (KeywordInsight). My insert statements don’t fail or throw any errors — they simply hang indefinitely. This behavior persists even for single-row inserts. It works on dev side and I deployed and the table is also visible on prod side but empty.

Setup
Python app using psycopg2 and a connection pool (SimpleConnectionPool)

The database and other tables work fine

Insert uses this structure (note: it's string-interpolated, not parameterized):

INSERT INTO "KeywordInsight" (
    "keyword", "volume12m", "volume12mNL", "volume12mBE", "volumeLastMonth",
    "listings", "sponsoredListings", "medianPrice", "medianReview", "medianReviews", "extraFilterOptions"
) VALUES (
    'example keyword', 100, 50, 50, 10,
    200, 5, 29.99, 4.5, 25, '{}'
) ON CONFLICT ("keyword") DO NOTHING;

INSERT INTO "KeywordInsight" (
    "keyword", "volume12m", "volume12mNL", "volume12mBE", "volumeLastMonth",
    "listings", "sponsoredListings", "medianPrice", "medianReview", "medianReviews", "extraFilterOptions"
) VALUES (
    'example keyword', 100, 50, 50, 10,
    200, 5, 29.99, 4.5, 25, '{}'
) ON CONFLICT ("keyword") DO NOTHING;

model KeywordInsight {
  id                 Int       @id @default(autoincrement())
  keyword            String    @unique

  volume12m          Int       @default(0)
  volume12mNL        Int       @default(0)
  volume12mBE        Int       @default(0)
  volumeLastMonth    Int       @default(0)
  listings           Int
  sponsoredListings  Int
  medianPrice        Float
  medianReview       Float
  medianReviews       Int
  extraFilterOptions String?   // JSON string (geëncodeerd), consistent met rest van systeem

  updatedAt          DateTime  @updatedAt
}

model KeywordInsight {
  id                 Int       @id @default(autoincrement())
  keyword            String    @unique

  volume12m          Int       @default(0)
  volume12mNL        Int       @default(0)
  volume12mBE        Int       @default(0)
  volumeLastMonth    Int       @default(0)
  listings           Int
  sponsoredListings  Int
  medianPrice        Float
  medianReview       Float
  medianReviews       Int
  extraFilterOptions String?   // JSON string (geëncodeerd), consistent met rest van systeem

  updatedAt          DateTime  @updatedAt
}

Symptoms
When this query runs, no result returns, and it never finishes.

I see the query listed in pg_stat_activity in state = 'active', but it stays there for hours.

Even if I forcibly kill the PID via pg_terminate_backend, it comes back on re-run.

This only happens on this table — other inserts (same connection style) work fine.

What I Tried
Killing all lingering sessions using pg_stat_activity

Restarting the script, terminals, and the machine itself

Checking for locks via pg_locks, pg_stat_activity, etc.

Using ON CONFLICT DO NOTHING in hopes it would skip collisions gracefully

Wasp•9mo ago•

15 replies

Sven

❓ PostgreSQL Insert Appears Stuck — No Error, Just Hanging / Deadlocking

Setup
Python app using psycopg2 and a connection pool (SimpleConnectionPool)

The database and other tables work fine

Insert uses this structure (note: it's string-interpolated, not parameterized):

INSERT INTO "KeywordInsight" (
    "keyword", "volume12m", "volume12mNL", "volume12mBE", "volumeLastMonth",
    "listings", "sponsoredListings", "medianPrice", "medianReview", "medianReviews", "extraFilterOptions"
) VALUES (
    'example keyword', 100, 50, 50, 10,
    200, 5, 29.99, 4.5, 25, '{}'
) ON CONFLICT ("keyword") DO NOTHING;

INSERT INTO "KeywordInsight" (
    "keyword", "volume12m", "volume12mNL", "volume12mBE", "volumeLastMonth",
    "listings", "sponsoredListings", "medianPrice", "medianReview", "medianReviews", "extraFilterOptions"
) VALUES (
    'example keyword', 100, 50, 50, 10,
    200, 5, 29.99, 4.5, 25, '{}'
) ON CONFLICT ("keyword") DO NOTHING;

model KeywordInsight {
  id                 Int       @id @default(autoincrement())
  keyword            String    @unique

  volume12m          Int       @default(0)
  volume12mNL        Int       @default(0)
  volume12mBE        Int       @default(0)
  volumeLastMonth    Int       @default(0)
  listings           Int
  sponsoredListings  Int
  medianPrice        Float
  medianReview       Float
  medianReviews       Int
  extraFilterOptions String?   // JSON string (geëncodeerd), consistent met rest van systeem

  updatedAt          DateTime  @updatedAt
}

model KeywordInsight {
  id                 Int       @id @default(autoincrement())
  keyword            String    @unique

  volume12m          Int       @default(0)
  volume12mNL        Int       @default(0)
  volume12mBE        Int       @default(0)
  volumeLastMonth    Int       @default(0)
  listings           Int
  sponsoredListings  Int
  medianPrice        Float
  medianReview       Float
  medianReviews       Int
  extraFilterOptions String?   // JSON string (geëncodeerd), consistent met rest van systeem

  updatedAt          DateTime  @updatedAt
}

❓ PostgreSQL Insert Appears Stuck — No Error, Just Hanging / Deadlocking

❓ PostgreSQL Insert Appears Stuck — No Error, Just Hanging / Deadlocking

Similar Threads

Similar Threads

Similar Threads