Check if row with value already exists in SQLite table
How do I check to see if row with a particular value already exists in a SQLite table?
My table has a String "name" column. I would like to check out if a particular name already exists in the another table row. I am still learning SQLite, but I think it is possible to do this with the cursor.
If you have a UNIQUE constraint on the name
column, you can use INSERT OR IGNORE (or insertWithOnConflict() in Android) to insert a row only if it does not already exist.
In the general case, to check whether a row exists, you have to run a SELECT query. However, there is a helper function for counting rows:
boolean nameExists(String name) {
SQLiteDatabase db = ...;
long count = DatabaseUtils.queryNumEntries(db,
"MyTable", "name = ?", new String[] { name });
return count > 0;
}
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