If a database table is created using SQL, if the CREATE command contains newlines, these control characters seem to be stored in the 'schema' part of the DB, with the result that when viewing the 'database structure' tab, the Schema column shows just the first field name, or in one observed case, the lower half of the table name and upper half of the field name !
The full schema is displayed correctly as a popup if the cursor is hovered over the entry, however.
I attach an SQL file to create a DB file with corrupted GUI Schema - use File -> Import -> Database from SQL file
SQL file for creating database displaying visually corrupted Schema
Looks like bug 1736028 is related to this one ...
this is something that must be recognized, SQLITE3 does not have the exact same structure as MySQL or PostgrSQL.
For example, MySQL requires that you put a collumn type of int or datetime with a length if needed, but sqlite3 has wont take either because it requires a full type of INTEGER or TEXT with no length and has no datetime field type.
I think you're issue is not "parsing" your file before importing to a sqlite3 database.