如何检查表是否存在于 Android SQLite 数据库中？

I know nothing about the Android SQLite API, but if you're able to talk to it in SQL directly, you can do this:

create table if not exists mytable (col1 type, col2 type);

Which will ensure that the table is always created and not throw any errors if it already existed.

You mentioned that you've created an class that extends SQLiteOpenHelper and implemented the onCreate method. Are you making sure that you're performing all your database acquire calls with that class? You should only be getting SQLiteDatabase objects via the SQLiteOpenHelper#getWritableDatabase and getReadableDatabase otherwise the onCreate method will not be called when necessary. If you are doing that already check and see if th SQLiteOpenHelper#onUpgrade method is being called instead. If so, then the database version number was changed at some point in time but the table was never created properly when that happened.

As an aside, you can force the recreation of the database by making sure all connections to it are closed and calling Context#deleteDatabase and then using the SQLiteOpenHelper to give you a new db object.

Yep, turns out the theory in my edit was right: the problem that was causing the onCreate method not to run, was the fact that SQLiteOpenHelper objects should refer to databases, and not have a separate one for each table. Packing both tables into one SQLiteOpenHelper solved the problem.

no such table exists: error is coming because once you create database with one table after that whenever you create table in same database it gives this error.

To solve this error you must have to create new database and inside the onCreate() method you can create multiple table in same database.

This is what I did:

/* open database, if doesn't exist, create it */
SQLiteDatabase mDatabase = openOrCreateDatabase("exampleDb.db", SQLiteDatabase.CREATE_IF_NECESSARY,null);


Cursor c = null;
boolean tableExists = false;
/* get cursor on it */
try
{
c = mDatabase.query("tbl_example", null,
null, null, null, null, null);
tableExists = true;
}
catch (Exception e) {
/* fail */
Log.d(TAG, tblNameIn+" doesn't exist :(((");
}


return tableExists;

Try this one:

public boolean isTableExists(String tableName, boolean openDb) {
if(openDb) {
if(mDatabase == null || !mDatabase.isOpen()) {
mDatabase = getReadableDatabase();
}


if(!mDatabase.isReadOnly()) {
mDatabase.close();
mDatabase = getReadableDatabase();
}
}


String query = "select DISTINCT tbl_name from sqlite_master where tbl_name = '"+tableName+"'";
try (Cursor cursor = mDatabase.rawQuery(query, null)) {
if(cursor!=null) {
if(cursor.getCount()>0) {
return true;
}
}
return false;
}
}

Although there are already a lot of good answers to this question, I came up with another solution that I think is more simple. Surround your query with a try block and the following catch:

catch (SQLiteException e){
if (e.getMessage().contains("no such table")){
Log.e(TAG, "Creating table " + TABLE_NAME + "because it doesn't exist!" );
// create table
// re-run query, etc.
}
}

It worked for me!

..... Toast t = Toast.makeText(context, "try... " , Toast.LENGTH_SHORT); t.show();

    Cursor callInitCheck = db.rawQuery("select count(*) from call", null);


Toast t2a = Toast.makeText(context, "count rows " + callInitCheck.getCount() , Toast.LENGTH_SHORT);
t2a.show();


callInitCheck.moveToNext();
if( Integer.parseInt( callInitCheck.getString(0)) == 0) // if no rows then do
{
// if empty then insert into call

.....

 // @param db, readable database from SQLiteOpenHelper


public boolean doesTableExist(SQLiteDatabase db, String tableName) {
Cursor cursor = db.rawQuery("select DISTINCT tbl_name from sqlite_master where tbl_name = '" + tableName + "'", null);


if (cursor != null) {
if (cursor.getCount() > 0) {
cursor.close();
return true;
}
cursor.close();
}
return false;
}

• sqlite maintains sqlite_master table containing information of all tables and indexes in database.
• So here we are simply running SELECT command on it, we'll get cursor having count 1 if table exists.

 public boolean isTableExists(String tableName) {
boolean isExist = false;
Cursor cursor = db.rawQuery("select DISTINCT tbl_name from sqlite_master where tbl_name = '" + tableName + "'", null);
if (cursor != null) {
if (cursor.getCount() > 0) {
isExist = true;
}
cursor.close();
}
return isExist;
}

Important condition is IF NOT EXISTS to check table is already exist or not in database

like...

String query = "CREATE TABLE IF NOT EXISTS " + TABLE_PLAYER_PHOTO + "("
+ KEY_PLAYER_ID + " TEXT,"
+ KEY_PLAYER_IMAGE + " TEXT)";
db.execSQL(query);

i faced that and deal with it by try catch as simple as that i do what i want in table if it not exist will cause error so catch it by exceptions and create it :)

SQLiteDatabase db=this.getWritableDatabase();
try{
db.execSQL("INSERT INTO o_vacations SELECT * FROM vacations");
db.execSQL("DELETE FROM vacations");
}catch (SQLiteException e){
db.execSQL("create table o_vacations (id integer primary key ,name text ,vacation text,date text,MONTH text)");
db.execSQL("INSERT INTO o_vacations SELECT * FROM vacations");
db.execSQL("DELETE FROM vacations");
}

Kotlin solution, based on what others wrote here:

    fun isTableExists(database: SQLiteDatabase, tableName: String): Boolean {
database.rawQuery("select DISTINCT tbl_name from sqlite_master where tbl_name = '$tableName'", null)?.use {
return it.count > 0
} ?: return false
}