Duplicator: Installing a Large Site When the Database Won't Import
Duplicator's installer stalls on big databases. How to use the two-stage and table-by-table options, or import the SQL manually.
Duplicator packages a whole WordPress site into an archive plus an installer.php. On a big site, the installer's database step is where things hang — it tries to run the entire SQL file inside one PHP request and hits the execution-time wall.
Turn on chunked database install
Duplicator's installer has database options that most people skip past. On the install screen, expand Advanced → Database and look for:
- Query Limit Size — lower it so each PHP request runs fewer statements (avoids timeouts)
- Mode: 'Chunk' rather than 'Single' — processes the SQL in batches across multiple requests
- Charset/Collation — set to match the destination to avoid 1273 collation errors
Chunk mode is the single most effective fix for a stalling installer on shared hosting.
When the installer still won't finish
If chunk mode isn't enough, do the database step by hand. Duplicator archives are just ZIP files — extract the database.sql inside:
unzip your-package_archive.zip 'database.sql' -d ./extracted/
# database.sql is the full dumpNow import that SQL the reliable way — via the command line, or split into chunks for phpMyAdmin — then point the extracted files at the freshly imported database.
Split Duplicator's database.sql
Pull the SQL out of the archive and import it in importable chunks when the installer gives up.
Open SQLSplitCommon installer errors
Frequently Asked Questions
Why does the Duplicator installer hang on the database step?
It tries to run the full SQL file within PHP's execution-time limit. On large sites this times out. Switch the installer to Chunk mode and lower the Query Limit Size so it processes the database in batches across multiple requests.
Can I import a Duplicator database manually?
Yes. The Duplicator archive is a ZIP containing database.sql. Extract it and import that file via the MySQL command line or by splitting it into chunks for phpMyAdmin, then connect the extracted site files to it.
How do I fix a collation error during Duplicator install?
Set the target charset and collation explicitly in the installer's Advanced → Database options to match your server (e.g. utf8mb4 / utf8mb4_unicode_ci), which avoids the MySQL-8 utf8mb4_0900_ai_ci mismatch.