TcaplusDB Client - select命令（查询主键索引）

TcaplusDB Client的使用方法参见文档。

1. 功能说明

根据用户指定的数据所有主键字段的值，查询整条数据的所有字段值或部分字段的值，如果没有匹配的记录，将会返回错误。

如果需要对查询到文件中的记录进行修改，再更新到服务端，请使用load命令。

请注意，对于List表，load命令会直接插入一条新记录，如果需要更新服务端的原有记录，请使用update命令并指定index。

请注意，保存查询结果的文件名不能以数字开头。

2. 启始版本

3.40.0

3. 命令语法

select key1, key2, key3, value1, value2 [into result.csv] from table [where key1 = 1 and key2 = "abc" and key3=1] [and -index = 1] [\P] [\G] [\S] [\N] [\A] [using tdr] [encode]
select * [into result.xml] from table [where key1 = 1 and key2 = "abc" and key3=1] [and -index = 1] using tdr [\P];

参数说明：

参数	PB表	TDR表	必填项
table	表格的名字	表格的名字	是
key	主键字段名，必须指定所有主键字段的值	主键字段名，必须指定所有主键字段的值	是
value	非主键字段名	非主键字段名	至少一个或 *
-index	Generic表：不支持 List表：如果指定“-index”会返回相同Key下的第index条记录，如果不指定 "-index", 则返回相同Key下的所有记录	Generic表：不支持 List表：如果指定“-index”会返回相同Key下的第index条记录，如果不指定 "-index", 则返回相同Key下的所有记录	否
\P	打印时延数据	打印时延数据	否
\G	竖排打印	竖排打印	否
\S	从从副本读取数据	从从副本读取数据	否，不填默认从主副本读取数据
\N	不打印字段名	不打印字段名	否，不填默认打印字段名
\A	将查询结果追加写到结果文件	将查询结果追加写到结果文件	否，不填默认将查询结果覆盖写到结果文件
into	输出数据到文件	输出数据到文件	否
using tdr	不支持	如果需要使用该参数，则在启动TcaplusDB Client时，就要通过启动参数指定与目标表对应的TDR文件	否
encode	不支持（回车字符或不可见字符已预处理）	指定该参数后，导出命令会将含有回车字符或不可见字符的string类型字段值进行BASE64编码后，再输出注意：只指定了`using tdr`参数时，该参数才生效	否

where语句中除了指定主键，在3.55.0之后版本，还支持使用 AND 结合更灵活的过滤条件，见详细语法。

4. 命令示例

表定义详见示例表定义。

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

tcaplus> select * into test.csv from test_table where gameid=1234 and itemid=12323 and name=testname;
1 records are stored to test.csv, select time: 10198 us

tcaplus> select * from test_table where gameid=1234 and itemid=12323 and name=testname \P \G;
gameid: 1234
itemid: 12323
name: "testname"
typeid: 0
Data: 9
uname: "ab"

API ----      -1us    --->ProxyFront----      10us    --->ProxyEnd---     364us    --->SvrMainStart
|                              |                             |                           |381us
|11380us                       |4138us                       |4104us                   SvrWorkerStart
|                              |                             |                           |61us
API <---   34197us    ----ProxyFront<---      24us    ----ProxyEnd<--    3298us    ----SvrWorkerEnd
1 records selectd, select time: 11380 us


tcaplus> select * into table_list.xml from table_list where uin=99 and name = "99" and key1=99 using tdr;
11 records are stored to table_list.xml, select time: 135299 us

tcaplus> select c_string from table_list where uin=99 and name = "99" and key1=99;
+---+----+----+--------+
|uin|name|key1|c_string|
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
|99 |"99"|99  |""      |
+---+----+----+--------+
|99 |"99"|99  |""      |
+---+----+----+--------+
|99 |"99"|99  |""      |
+---+----+----+--------+
|99 |"99"|99  |""      |
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
11 records selectd, select time: 102572 us

tcaplus> select c_string from table_list where uin=99 and name = "99" and key1=99 and -index=9;
+---+----+----+--------+
|uin|name|key1|c_string|
+---+----+----+--------+
|99 |"99"|99  |" "     |
+---+----+----+--------+
1 records selectd, select time: 9886 us

tcaplus> select * from table_list_bin where uin=1 and name="3" encode;
+------+---+------+-----+-----+-----+------+------+------------+------------+-------------+
|-index|uin|name  |level|count|items|name_1|name_2|binary_count|binary      |single_struct|
+------+---+------+-----+-----+-----+------+------+------------+------------+-------------+
|0     |1  |"Mw=="|1    |0    |0x   |""    |""    |5           |0x1232123443|0x           |
+------+---+------+-----+-----+-----+------+------+------------+------------+-------------+
|1     |1  |"Mw=="|1    |0    |0x   |""    |""    |5           |0x1232123443|0x           |
+------+---+------+-----+-----+-----+------+------+------------+------------+-------------+
2 records selected, select time: 4333 us

tcaplus> select * from table_list_bin where uin=1 and name="3";
+------+---+----+-----+-----+-----+------+------+------------+------------+-------------+
|-index|uin|name|level|count|items|name_1|name_2|binary_count|binary      |single_struct|
+------+---+----+-----+-----+-----+------+------+------------+------------+-------------+
|0     |1  |"3" |1    |0    |0x   |""    |""    |5           |0x1232123443|0x           |
+------+---+----+-----+-----+-----+------+------+------------+------------+-------------+
|1     |1  |"3" |1    |0    |0x   |""    |""    |5           |0x1232123443|0x           |
+------+---+----+-----+-----+-----+------+------+------------+------------+-------------+
2 records selected, select time: 4335 us