Develop Reference

Can't find the syntax error in this SQLite statement

I am writing an Android app and need a database for it. I will have three tables but only managed to make one right now. I do them in the console to debug and to implement them in my Javacode later. The following statements were succesfull:
sqlite3 progressapp.db
CREATE TABLE Z_Type(_Z_T_ID INTEGER PRIMARY KEY NOT NULL,
Description TEXT NOT NULL, Unit TEXT NOT NULL);
But now I want to refference the PK of T_Type in my other table:
CREATE TABLE goals (_Z_id INTEGER PRIMARY KEY NOT NULL, Title TEXT NOT NULL,
Type INTEGER NOT NULL, FOREIGN KEY(Type) REFERENCES Z_Type(_Z_T_ID),
Timeframe TEXT, Goaldate INTEGER);
Is Type INTEGER NOT NULL, FOREIGN KEY(Type) REFERENCES Z_Type(_Z_T_ID) a valid SQLite Statement in Android? It says "Error: near "Timeframe": syntax error" But I simply can't find it due to lack with SQL Experience I guess.
Is there a better way to reference the FK maybe?

Try this:
CREATE TABLE goals (_Z_id INTEGER PRIMARY KEY NOT NULL, Title TEXT NOT NULL,
Type INTEGER NOT NULL,Timeframe TEXT, Goaldate INTEGER, FOREIGN KEY(Type) REFERENCES Z_Type(_Z_T_ID));
I think that the order is important.
For further documentation you could visit sqlite.org/foreignkeys.html

You can define the reference as part of the column definition
CREATE TABLE goals (_Z_id INTEGER PRIMARY KEY NOT NULL, Title TEXT NOT NULL,
Type INTEGER NOT NULL REFERENCES Z_Type(_Z_T_ID),
Timeframe TEXT, Goaldate INTEGER);

In a sqlite CREATE TABLE statement, column definitions come first and table constraints only after that.
FOREIGN KEY(Type) REFERENCES Z_Type(_Z_T_ID) is a table constraint that should go at the end.

Android: mySQL, create table command

I'm trying to create a table and I've tried so many times to figure this out... for some reason it won't accept this.. it's saying something about the auto_increment
create table if not exists Assignments(
id auto_increment primary key,
class_name VARCHAR(30),
assignment_name VARCHAR(30) not null,
due_date VARCHAR(30) not null,
notes VARCHAR(30));
whats the problem?
EDIT: i am trying to use SQLite eventually but this command was written on my mySQL thru WAMP

First of all, Android uses SQLite, so your mysql tag is slightly incorrect unless I'm missing something you're doing.
Secondly, you would say
CREATE TABLE ASSIGNMENTS(id INTEGER PRIMARY KEY, class_name TEXT, assignment_name TEXT NOT NULL, due_date TEXT NOT NULL, notes TEXT);
"autoincrement" is handled automatically if you set your primary key as an INTEGER type, even though under the covers SQLite uses strings for everything
reference: SQLite datatypes
further reference: INTEGER PRIMARY KEY
Even more reference: "If an INSERT statement attempts to insert a NULL value into a rowid or integer primary key column, the system chooses an integer value to use as the rowid automatically. A detailed description of how this is done is provided separately."

It is autoincrement, not auto_increment

INSERT OR IGNORE table with AUTOINCREMENT key in Android

I am trying to insert data to a new empty table. But I keep getting error (error code 19: constraint failed). I think the problem may caused by 'INTEGER PRIMARY KEY AUTOINCREMENT'. Here is my code:
database.execSQL("CREATE TABLE IF NOT EXISTS contacts (cid INTEGER PRIMARY KEY AUTOINCREMENT, name varchar NOT NULL, user varchar NOT NULL, UNIQUE(user) ON CONFLICT REPLACE)");
...
String sql = "INSERT OR IGNORE INTO contacts ( name , user) VALUES (?, ?)";
database.beginTransaction();
SQLiteStatement stmt = database.compileStatement(sql);
stmt.bindString(1, name);
stmt.bindString(2, entry.getUser());
int i = (int)stmt.executeInsert();
stmt.execute();
stmt.clearBindings();
stmt.close();
// error: 06-11 20:50:42.295: E/DB(12978): android.database.sqlite.SQLiteConstraintException: error code 19: constraint failed
Anyone knows what wrong with the sql statement? How can I solve this problem? Thanks
I have read few articles on stackoverflow. But cannot find anyone post related to 'insert or replace' + 'INTEGER PRIMARY KEY AUTOINCREMENT'.

I think your code is doing exactly what it is supposed to be doing. Reading over your code it looks like you want it to ignore inserts where there is already something inserted. The error you are receiving is telling you that the insert has failed.
If you use INSERT IGNORE, then the row won't actually be inserted if it results in a duplicate key. But the statement won't generate an
error. It generates a warning instead. These cases include:
Inserting a duplicate key in columns with PRIMARY KEY or UNIQUE
constraints. Inserting a NULL into a column with a NOT NULL
constraint. Inserting a row to a partitioned table, but the values you
insert don't map to a partition. - "INSERT IGNORE" vs "INSERT ... ON DUPLICATE KEY UPDATE"
I would recommend catching the SQLiteConstraintException or check before inserting to see if the data is already there. If you need some ideas on how to check if data has been inserted let me know, I have had to do this before. Hope this helps.

There is a good begining to end example of SQLite on Android written by Lars Vogella here
Inside there and down a little ways here is the string that he uses for creating a table:
// Database creation sql statement
private static final String DATABASE_CREATE = "create table "
+ TABLE_COMMENTS + "(" + COLUMN_ID
+ " integer primary key autoincrement, " + COLUMN_COMMENT
+ " text not null);";
I have not tried either his or yours just now but a few things I noticed that differ between his and yours are:
He has no space between the table name and the opening parenthesis
He has a semicolon inside of the SQL string. after the closing parenthesis.
I am not certain if those will fix it for you, but it would probably be a good start.

Duplicate Entries in SQLite

I am fetching and storing phone numbers and contact names in a SQLite DB from an Android phone. Now my problem is that whenever I refresh/reload the app the SQL entries (phone and contacts) are inserted again and again giving rise to duplicate entries. How to stop this, I am using Phonegap, by the way!
I am using this simple code to populate the DB
tx.executeSql('CREATE TABLE IF NOT EXISTS details (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, phone TEXT)');
But it is causing double entries.

Stopping this can be as easy as defining a two field primary key, like this :
CREATE TABLE contacts(
name CHAR(10) NOT NULL,
address INTEGER,
phone INTEGER NOT NULL,
song VARCHAR(255),
PRIMARY KEY (name, phone)
)
This key will ensure no entry in the database has the same name and phone.
Hope this helps !

It will solve the duplicate entry problem:
sampleDB.execSQL("INSERT OR REPLACE INTO measure_table (measure) " + "VALUES ( '" + "Length" + "')");

Column not created in SQLITE3 table

Now I have a weird problem, I've done all kinds of test and I believe I'm seeing something weird.
I create three tables in SQLiteOpenHelper:
public void onCreate(SQLiteDatabase db) {
try {
db.execSQL(TABLE_CHANNELS_CREATE);
db.execSQL(TABLE_FEEDS_CREATE);
db.execSQL(TABLE_FEEDMAP_CREATE);
}
catch (SQLiteException e){
Toast.makeText(mContext, e.getMessage(), Toast.LENGTH_LONG).show();
}
}
The CREATE statements for the three tables follow:
CREATE TABLE IF NOT EXISTS IRChannels (
ChannelId INTEGER PRIMARY KEY,
ChannelHash TEXT NOT NULL,
ChannelTitle TEXT NOT NULL,
ChannelDesc TEXT, ChannelLink TEXT);
CREATE TABLE IF NOT EXISTS IRFeeds (
FeedId INTEGER PRIMARY KEY,
FeedHash TEXT NOT NULL,
FeedTitle TEXT NOT NULL,
FeedDescription TEXT,
FeedLink TEXT);
CREATE TABLE IF NOT EXISTS IRFeedMap (
ChannelHash_FK TEXT NOT NULL,
FeedHash_FK TEXT NOT NULL,
FOREIGN KEY (ChannelHash_FK) REFERENCES IRChannels (ChannelHash),
FOREIGN KEY (FeedHash_FK) REFERENCES IRFeeds (FeedHash));
The problem is apparently the column FeedHash in IRFeeds is not created while others are. I'm looking at the output in sqlite3 command prompt;
sqlite> .schema
CREATE TABLE IRChannels (
ChannelId INTEGER PRIMARY KEY,
ChannelHash TEXT NOT NULL,
ChannelTitle TEXT NOT NULL,
ChannelDesc TEXT,
ChannelLink TEXT);
CREATE TABLE IRFeedMap (
ChannelHash_FK TEXT NOT NULL,
FeedHash_FK TEXT NOT NULL,
FOREIGN KEY (ChannelHash_FK) REFERENCES IRChannels (ChannelHash),
FOREIGN KEY (FeedHash_FK) REFERENCES IRFeeds (FeedHash));
CREATE TABLE IRFeeds (
FeedId INTEGER PRIMARY KEY,
FeedHash TEXT NOT NULL,
FeedTitle TEXT NOT NULL,
FeedDescription TEXT,
FeedLink TEXT);
This does list the FeedHash column in IRFeeds. However, when I execute
sqlite> select * from IRFeeds where FeedHash='';
SQL error: no such column: FeedHash
All other columns do not give such errors. This condition is causing my code to fail unexpectedly as well. What could I be missing?
sqlite> select * from IRFeeds where FeedID=1;
sqlite> select * from IRFeeds where FeedTitle='';
sqlite> select * from IRFeeds where FeedDescription='';
sqlite> select * from IRFeeds where FeedLink='';
No errors above when I execute select statement for other columns.

There is no error in your SQL. I tested and everything was created properly. Also your SQL query did not cause no such column error. So try to delete the database with context.deleteDatabase(databaseName); and try again.

After an entire day of struggle, I managed to isolate why the problem triggers. Still don't know why, but it does fix the problem. The problems occurs because of the following table which has foreign keys on the other two tables:
CREATE TABLE IRFeedMap (
ChannelHash_FK TEXT NOT NULL,
FeedHash_FK TEXT NOT NULL,
FOREIGN KEY (ChannelHash_FK) REFERENCES IRChannels (ChannelHash),
FOREIGN KEY (FeedHash_FK) REFERENCES IRFeeds (FeedHash));
Changing the column names of foreign key columns to be the same as the column they reference fixes the problem. I changed the statement above to:
CREATE TABLE IRFeedMap (
ChannelHash TEXT NOT NULL,
FeedHash TEXT NOT NULL,
FOREIGN KEY (ChannelHash) REFERENCES IRChannels (ChannelHash),
FOREIGN KEY (FeedHash) REFERENCES IRFeeds (FeedHash));
And voila! Sanity was restored. Beats me.

In my case I was using a SQLite reserved word (column, that was)
I ended up in this SO question, so maybe it helps others in my situation