Tablestore:Query information about a table

Prerequisites

Before you begin, ensure that you have:

• A Tablestore client initialized. For more information, see Initialize a Tablestore client

Usage notes

The SQL query feature requires Tablestore SDK for .NET V5.0.0 or later.

For version details, see Version history of Tablestore SDK for .NET .

Parameters

Examples

The following example runs the describe test_table statement and prints the schema and each row of the result set. Each row contains six columns in this order: field name, field type, null constraint, default value, primary key flag, and partition key flag.

/// <summary>
/// Query information about a table.
/// </summary>
/// <param name="otsClient"></param>
public static void DescribeTable(OTSClient otsClient)
{
    SQLQueryRequest sqlQueryRequest = new SQLQueryRequest("describe test_table");

    SQLQueryResponse sqlQueryResponse = otsClient.SQLQuery(sqlQueryRequest);

    // Print the table schema as JSON.
    SQLTableMeta sqlTableMeta = sqlQueryResponse.GetSQLResultSet().GetSQLTableMeta();
    Console.WriteLine(JsonConvert.SerializeObject(sqlTableMeta.GetSchema()));

    // Iterate over the result set. Each row contains six columns:
    // index 0: field name, 1: field type, 2: null constraint,
    // 3: default value, 4: primary key flag, 5: partition key flag.
    ISQLResultSet resultSet = sqlQueryResponse.GetSQLResultSet();
    while (resultSet.HasNext())
    {
        ISQLRow row = resultSet.Next();
        Console.WriteLine(row.GetString(0) + " " + row.GetString(1) + " " + row.GetString(2) + " " +
                          row.GetString(3) + " " + row.GetString(4) + " " + row.GetString(5));
    }
}