Query data with SQL

Tablestore SDK for Python executes a SELECT statement to query data from a mapping table.

Prerequisites

Install Tablestore SDK for Python and initialize a client.
SQL query requires version 5.4.2 or later. We recommend that you use the latest version.
For the data table that you want to access, create a mapping table.

Description

Call the exe_sql_query method to execute a SELECT statement and query data from a mapping table.

def exe_sql_query(self, query)

The following example queries the row whose primary key is row1 from example_table.

query = (
    "SELECT pk, long_value, double_value, string_value, bool_value "
    "FROM example_table WHERE pk = 'row1' LIMIT 20"
)
row_list, table_capacity_units, search_capacity_units = client.exe_sql_query(query)

for row in row_list:
    print(dict(row.attribute_columns))

Parameters

The exe_sql_query method contains the following parameter.

Name	Type	Description
query (required)	String	The `SELECT` statement to execute. The statement specifies the mapping table, columns to return, query conditions, and row limit.

Response

The exe_sql_query method returns a tuple that contains the following elements.

Element	Type	Description
`row_list`	List[Row]	A list of result rows. The `attribute_columns` attribute of each `Row` object contains column names and values.
`table_capacity_units`	List[Tuple]	Read and write CUs consumed by data tables. Each tuple contains a table name and a `CapacityUnit` object.
`search_capacity_units`	List[Tuple]	Read and write CUs consumed by search indexes. Each tuple contains a search index name and a `CapacityUnit` object.