[sqlite] 判断表、视图是否存在及常用C#操作语句

1,判断表是否存在：

SELECT name, sql FROM sqlite_master WHERE type="table" AND name = "Dom" 

结果如下：

2.判断视图是否存在：

SELECT count(*) FROM sqlite_master WHERE type = "view" AND name = "myView"

结果如下：

type='view'判断视图.结果>0就是有这个视图 

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另附C#操作的常用代码：

 

    DataTable table = conn.GetSchema("TABLES");
    if (table != null && table.Rows.Count > 0)
       {
           string tableName = table.Rows[0]["TABLE_NAME"].ToString();
           DataTable schemaTable = GetReaderSchema(tableName, conn);
       }

　　

    private DataTable GetReaderSchema(string tableName, SQLiteConnection connection)
    {
        DataTable schemaTable = null;
        IDbCommand cmd = new SQLiteCommand();
        cmd.CommandText = string.Format("select * from [{0}]", tableName);
        cmd.Connection = connection;
        using (IDataReader reader = cmd.ExecuteReader(CommandBehavior.KeyInfo | CommandBehavior.SchemaOnly))
        {
            schemaTable = reader.GetSchemaTable();
        }
        return schemaTable;
    }
 
  

　　

    foreach (DataRow dr in schemaTable.Rows)
    {
        ColumnInfo info = new ColumnInfo();
        info.Name = new NameElement(dr["ColumnName"].ToString());
        info.Ordinal = Convert.ToInt32(dr["ColumnOrdinal"].ToString());
        info.AllowDBNull = (bool)dr["AllowDBNull"];
        info.MaxLength = Convert.ToInt32(dr["ColumnSize"].ToString());
        info.DataTypeId = Convert.ToInt32(dr["ProviderType"].ToString());
        info.DataType = dr["DataTypeName"].ToString().Trim();
        info.AutoIncrement = (bool)dr["IsAutoIncrement"];
        info.IsPrimaryKey = (bool)dr["IsKey"];
        info.Unique = (bool)dr["IsUnique"];
        info.IsReadOnly = (bool)dr["IsReadOnly"];
        string netType = dr["DataType"].ToString();
 
        list.Add(info.Name.Name.ToString(), info);
    }