• Ivy Seo

PostgreSQL check if exists() in C#

A function that checks if the table already exists in the database:


private static bool CheckIfTableExists()

{ // check if the table already exists in database -> return true

bool tableExist = false;


// connect to postgresql

var cs = "Host=epic-works-pg.postgres.database.azure.com; Username=username@epic-works-pg; Password=YourPassword; Database=epic-works-test";


using var con = new NpgsqlConnection(cs);

con.Open();


// SELECT if table EXISTS

string sql = "SELECT EXISTS (SELECT 1 FROM pg_tables WHERE tablename = 'm7_data_table')";

using var cmd = new NpgsqlCommand(sql, con);


using NpgsqlDataReader rdr = cmd.ExecuteReader();


while (rdr.Read())

{

Console.WriteLine("table exist bool: {0}", rdr.GetBoolean(0));

tableExist = rdr.GetBoolean(0);

}

return tableExist;

}


#C #Postgresql

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