MySQL Connector/NET Developer Guide
The GetSchema()
method of the connection object
can be used to retrieve schema information about the database
currently connected to. The schema information is returned in the
form of a DataTable
. The schema information is
organized into a number of collections. Different forms of the
GetSchema()
method can be used depending on the
information required. There are three forms of the
GetSchema()
method:
GetSchema()
- This call will return a list
of available collections.
GetSchema(String)
- This call returns
information about the collection named in the string
parameter. If the string “MetaDataCollections” is
used then a list of all available collections is returned.
This is the same as calling GetSchema()
without any parameters.
GetSchema(String, String[])
- In this call
the first string parameter represents the collection name, and
the second parameter represents a string array of restriction
values. Restriction values limit the amount of data that will
be returned. Restriction values are explained in more detail
in the
Microsoft
.NET documentation.
The collections can be broadly grouped into two types: collections that are common to all data providers, and collections specific to a particular provider.
Common Collections. The following collections are common to all data providers:
MetaDataCollections
DataSourceInformation
DataTypes
Restrictions
ReservedWords
Provider-Specific Collections. The following are the collections currently provided by Connector/NET, in addition to the common collections shown previously:
Databases
Tables
Columns
Users
Foreign Keys
IndexColumns
Indexes
Foreign Key Columns
UDF
Views
ViewColumns
Procedure Parameters
Procedures
Triggers
Example Code. A list of available collections can be obtained using the following code:
using System; using System.Data; using System.Text; using MySql.Data; using MySql.Data.MySqlClient; namespace ConsoleApplication2 { class Program { private static void DisplayData(System.Data.DataTable table) { foreach (System.Data.DataRow row in table.Rows) { foreach (System.Data.DataColumn col in table.Columns) { Console.WriteLine("{0} = {1}", col.ColumnName, row[col]); } Console.WriteLine("============================"); } } static void Main(string[] args) { string connStr = "server=localhost;user=root;database=world;port=3306;password=******"; MySqlConnection conn = new MySqlConnection(connStr); try { Console.WriteLine("Connecting to MySQL..."); conn.Open(); DataTable table = conn.GetSchema("MetaDataCollections"); //DataTable table = conn.GetSchema("UDF"); DisplayData(table); conn.Close(); } catch (Exception ex) { Console.WriteLine(ex.ToString()); } Console.WriteLine("Done."); } } }
Further information on the GetSchema()
method
and schema collections can be found in the
Microsoft
.NET documentation.