String selection = null // this will select all rowsĬursor cursor = db.query(MyDatabaseHelper. The documentation saysĬolumns Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.Įxample SQLiteDatabase db = mHelper.getReadableDatabase() Selection Passing null will return all rows for the given table.Īnd while you can also pass in null for the column parameter to get all of the columns (as in the one-liner above), it is better to only return the columns that you need. So I think I have to use DataSet to combine all DataTable(s) and send it to object as parameter. The documentation for query says that you can just pass in null to the selection parameter to get all the rows. Now I use method in C to read table from SQLite database into DataTable, but I want to send all table into other object. The other answers use rawQuery, but you can use Android's built in SQLiteDatabase. Cursor cursor = db.query(TABLE_NAME, null, null, null, null, null, null, null) The APIs youll need to use a database on Android are available in the package. So I'm storing 7 booleans in one integer with room for more.If you want every column and every row, then just pass in null for the SQLiteDatabase column and selection parameters. If (has(inp,"closeCaptioned='true'") > 0) misc is an unsigned char initialized to 0. inp is the input string to this function. has() is a function that returns 1 if the 2nd string is in the first one. One character really.Ī C example from what I'm working on now. So 7 bits, or an integer with a maximum of 127. I'm just writing something for storing TV schedule data from Schedules Direct and I have the binary or yes/no fields: stereo, hdtv, new, ei, close captioned, dolby, sap in Spanish, season premiere. Within each digit 4 is read, 2 is write, 1 is execute so 7 is all of them like binary 111. Sqlite> select mycolumn, typeof(mycolumn) from foo Īnd some that will fail: sqlite> INSERT INTO foo VALUES("-1") īut,if you want to store a bunch of them you could bit-shift them and store them all as one int, a little like unix file permissions/modes.įor mode 755 for instance, each digit refers to a different class of users: owner, group, public. Here are some example INSERTs that will work: (note how strings and floating point numbers are parsed as integers) sqlite> INSERT INTO foo VALUES(0) SQLiteDatabase database getBaseContext (). I manage to get this, but I also get temporary table names like androidmetadata and sqlitesequence. Note that CHECK constraints have been supported since SQLite 3.3.0 (2006). I am trying to get a list of table names from an SQLite database. The use of the type name BOOLEAN here is for readability, to SQLite it's just a type with NUMERIC affinity. But the log.e show the information: : no such table: types: But, I really have this table. Omit the NOT NULL if you want to allow NULL in addition to 0 and 1. I open a sqlite database and use rawquery to get data. Caution: Although these APIs are powerful, they are fairly low-level and require a great deal of time and effort to use: There is no compile-time verification of raw SQL queries. You could declare the column type like this: CREATE TABLE foo(mycolumn BOOLEAN NOT NULL CHECK (mycolumn IN (0, 1))) The APIs you'll need to use a database on Android are available in the package. In SQLite the best you can do is use the integers 0 and 1 to represent false and true.
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