Search & replace URLs in WordPress SQL files.
cat example-from.com.sql | search-replace example-from.com example-to.com > example-to.com.sql
Migrating WordPress databases often requires replacing domain names. This is a complex operation because WordPress stores PHP serialized data, which encodes string lengths. The common method uses PHP to unserialize the data, do the search/replace, and then re-serialize the data before writing it back to the database. Here we replace strings in the SQL file and then fix the string lengths.
Replacing strings in a SQL file can be dangerous. We have to be careful not to modify the structure of the file in a way that would corrupt the file. For this reason, we're limiting the search domain to roughly include characters that can be used in domain names. Since the most common usage for search-replace is changing domain names or switching http: to https:, this is an easy way to avoid otherwise complex issues.