Match phrase query is similar to match query, except match phrase query evaluates the positions of tokens. A row meets the query condition only when the order and positions of the tokens in the row match the order and positions of the tokens that are contained in the keyword. If the tokenization method for the column that you want to query is fuzzy tokenization, match phrase query is performed at a lower latency than wildcard query.
Prerequisites
- An OTSClient instance is initialized. For more information, see Initialization.
- A data table is created. Data is written to the table.
- A search index is created for the data table. For more information, see Create search indexes.
Parameters
| Parameter | Description |
|---|---|
| FieldName | The name of the column that you want to match. You can perform match phrase queries on TEXT columns. |
| Text | The keyword that is used to match the column values when you perform a match phrase query. If the column that you want to match is a TEXT column, the keyword is tokenized into multiple tokens based on the analyzer type that you specify when you create the search index. By default, single-word tokenization is performed if you do not specify the analyzer type when you create the search index. For example, if you query the phrase "this is", "..., this is tablestore" and "this is a table" are returned. "this table is ..." and "is this a table" are not returned. |
| Query | The query type. Set the query type to MatchPhraseQuery. |
| TableName | The name of the table. |
| IndexName | The name of the search index. |
| GetTotalCount | Specifies whether to return the total number of rows that meet the query conditions. The default value of this parameter is false, which indicates that the total number of rows that meet the query conditions is not returned. If you set this parameter to true, the query performance is compromised. |
| ColumnsToGet | Specifies whether to return all columns of each row that meets the query conditions. You can configure ReturnAll, Columns, and ReturnAllFromIndex for this parameter. The default value of ReturnAll is false, which indicates that not all columns are returned. You can use one of the following methods to specify the columns that you want to return. If you do not use the following methods to specify the columns that you want to return, only the primary key columns are returned.
If you set ReturnAll to true, all columns are returned. |
Examples
/// <summary>
/// Use match phrase query to search the table for rows in which the value of the Text_type_col column matches "Tablestore SearchIndex" and return the total number of rows that meet the query conditions.
/// </summary>
/// <param name="otsClient"></param>
public static void MatchPhraseQuery(OTSClient otsClient)
{
var searchQuery = new SearchQuery();
// Set the query type to MatchPhraseQuery.
searchQuery.Query = new MatchPhraseQuery(Text_type_col, "Tablestore SearchIndex");
// Specify that the total number of rows that meet the query conditions is returned.
searchQuery.GetTotalCount = true;
var request = new SearchRequest(TableName, IndexName, searchQuery);
// You can use the ColumnsToGet parameter to specify the columns that you want to return, specify that all columns are returned, or specify that all columns in the search index are returned. If you do not configure this parameter, only the primary key columns are returned.
request.ColumnsToGet = new ColumnsToGet()
{
// Specify that all columns in the search index are returned.
ReturnAllFromIndex = true
// Specify the columns that you want to return.
//Columns = new List<string>() { Long_type_col, Text_type_col, Keyword_type_col }
// Specify that all columns are returned.
//ReturnAll = true
};
var response = otsClient.Search(request);
Console.WriteLine("Total Count:" + response.TotalCount); // Specify that the total number of rows that meet the query conditions instead of the number of rows that are returned is displayed.
}