I'm getting an "Invalid Character Constant" under the " 'D " just after UPDATE. Any Ideas? ORIGINAL :
public Cursor fetchAllJournals(String sort) { mDb.rawQuery(UPDATE 'DATABASE_JOURNAL_TABLE' SET 'KEY_JOURNAL_NOTES' = (SELECT COUNT(*) FROM 'DATABASE_HOMES_TABLE' WHERE 'DATABASE_JOURNAL_TABLE'.'KEY_JROWID' = 'DATABASE_HOMES_TABLE'.'KEY_HOME_JOURNALID') ) return mDb.query(DATABASE_JOURNAL_TABLE, new String[] {KEY_JROWID, KEY_JOURNAL_TITLE, KEY_JOURNAL_NOTES, KEY_JDATE},null , null, null, null, sort ,null); }
ANSWER:
public Cursor fetchAllJournals(String sort) { mDb.execSQL("UPDATE "+DATABASE_JOURNAL_TABLE+" SET "+KEY_JOURNAL_NOTES+" " + " = (SELECT COUNT(*) FROM "+DATABASE_HOMES_TABLE+" WHERE " 开发者_开发问答 +DATABASE_JOURNAL_TABLE+"."+KEY_JROWID+" = "+DATABASE_HOMES_TABLE +"." + KEY_HOME_JOURNALID+")"); return mDb.query(DATABASE_JOURNAL_TABLE, new String[] {KEY_JROWID, KEY_JOURNAL_TITLE, KEY_JOURNAL_NOTES, KEY_JDATE},null , null, null, null, sort ,null); }
The invalid character constant in this case is 'DATABASE_JOURNAL_TABLE'. Single quotes in Java define a character constant, i.e. one character, e.g. 'a' or 'b' or '!'. 'DATABASE_JOURNAL_TABLE' is a string of them so you have to use a String literal and double quotes, i.e. "prefix "+DATABASE_JOURNAL_TABLE+" suffix".
Try this:
public Cursor fetchAllJournals(String sort) {
mDb.rawQuery("UPDATE "+DATABASE_JOURNAL_TABLE+" SET "+KEY_JOURNAL_NOTES+" = (SELECT COUNT(*) FROM "+DATABASE_HOMES_TABLE+"WHERE "+DATABASE_JOURNAL_TABLE+"."+KEY_JROWID+" =+"DATABASE_HOMES_TABLE"+."+KEY_HOME_JOURNALID+")");
return mDb.query(DATABASE_JOURNAL_TABLE, new String[] {KEY_JROWID, KEY_JOURNAL_TITLE, KEY_JOURNAL_NOTES, KEY_JDATE},null , null, null, null, sort ,null);
}
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