TcaplusDB Client - Select Command (Query Local Indexes)

For TcaplusDB Client Instructions, see Document.

1. Function Descriptions

Query all data under the index entry according to the values of all index fields of a local index specified by the user. It supports to query all field values or partial field values of the all data. If there are no matching records, an error will be returned.

Before querying a local index, you must first confirm that the corresponding Local Index has been defined in the table.

If you need to modify the records in the queried file and then update them to the server, use the load command.

Please note that for the List table, the load command will directly insert a new record. If you need to update the original record on the server, use the update command and specify the index.

Please note that the file name for saving query results cannot start with a number.

2. Initial Version

3.40.0

3. Command Syntax

select index_key1, index_key2, key3, value1, value2 [into result.csv] from table [where index_key1 = 1 and index_key2 = "abc"] [\P] [\G] [\S] [using tdr] [encode]
select * [into result.xml] from table [where index_key1 = 1 and index_key2 = "abc"] using tdr [\P];

Parameter description:

Parameter	PB Table	TDR Table	Required
table	Table name	Table name	Yes
index_key	Index field name. The values of all index fields must be specified	Index field name. The values of all index fields must be specified	Yes
key/value	field name	field name	At least one or *
\P	Print delay data	Print delay data	No
\G	Vertical printing	Vertical printing	No
\S	Read data from copy	Read data from copy	No. If not specified, it is the default to read data from the primary replica
\N	Do not print field names	Do not print field names	No. If not specified, it is the default to print field names
\A	Append query results to a file	Append query results to a file	No. If not specified, it is the default to overwrite the query results to a file
into	Export data to file	Export data to file	No
using tdr	Do not support	If this parameter is required, it needs to specify the TDR file corresponding to the target table through the startup parameters at the time of starting the TcaplusDB Client.	No
encode	Not supported (carriage return or invisible characters have been preprocessed)	After specifying this parameter, the dump command will encode the string type field value containing carriage return characters or invisible characters into BASE64 before outputting. Note: This parameter takes effect only when it is specified `using tdr`	No

In addition to specifying the partial keys in the where statement, versions after 3.55.0 also support the use of AND, combined with more flexible filter conditions. See Detailed Syntax.

4. Command Example

See Table Definition Example for table definition.

tcaplus> select * from test_table where gameid=1234 and itemid=12323;
+------+------+----------+------+----+-----+
|gameid|itemid|name      |typeid|Data|uname|
+------+------+----------+------+----+-----+
|1234  |12323 |"testname"|0     |9   |"ab" |
+------+------+----------+------+----+-----+
1 records selectd, select time: 9802 us

tcaplus> select uname from test_table where gameid=1234 and itemid=12323;
+------+------+----------+-----+
|gameid|itemid|name      |uname|
+------+------+----------+-----+
|1234  |12323 |"testname"|"ab" |
+------+------+----------+-----+
1 records selectd, select time: 9457 us