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+---
+title: Batch INSERT Statements for Bulk Data
+impact: MEDIUM
+impactDescription: 10-50x faster bulk inserts
+tags: batch, insert, bulk, performance, copy
+---
+
+## Batch INSERT Statements for Bulk Data
+
+Individual INSERT statements have high overhead. Batch multiple rows in single statements or use COPY.
+
+**Incorrect (individual inserts):**
+
+```sql
+-- Each insert is a separate transaction and round trip
+insert into events (user_id, action) values (1, 'click');
+insert into events (user_id, action) values (1, 'view');
+insert into events (user_id, action) values (2, 'click');
+-- ... 1000 more individual inserts
+
+-- 1000 inserts = 1000 round trips = slow
+```
+
+**Correct (batch insert):**
+
+```sql
+-- Multiple rows in single statement
+insert into events (user_id, action) values
+  (1, 'click'),
+  (1, 'view'),
+  (2, 'click'),
+  -- ... up to ~1000 rows per batch
+  (999, 'view');
+
+-- One round trip for 1000 rows
+```
+
+For large imports, use COPY:
+
+```sql
+-- COPY is fastest for bulk loading
+copy events (user_id, action, created_at)
+from '/path/to/data.csv'
+with (format csv, header true);
+
+-- Or from stdin in application
+copy events (user_id, action) from stdin with (format csv);
+1,click
+1,view
+2,click
+\.
+```
+
+Reference: [COPY](https://www.postgresql.org/docs/current/sql-copy.html)