The YugabyteDB SQL shell (ysqlsh) provides a CLI for interacting with YugabyteDB using YSQL
The -c flag pecifies that ysqlsh is to execute the given command string, where the command can be a meta-command or some SQL statement.
Example:
[root@localhost ~]# ysqlsh -U yugabyte -c "\d t;"
Table "public.t"
Column | Type | Collation | Nullable | Default
--------+-------------------+-----------+----------+---------
c1 | integer | | not null |
c2 | character varying | | |
Indexes:
"t_pkey" PRIMARY KEY, lsm (c1 HASH)
[root@localhost ~]# ysqlsh -U yugabyte -c "SELECT * FROM t;"
c1 | c2
----+----
1 | A
2 | B
3 | C
(3 rows)
Unfortunatley we cannot combine meta-commands and SQL in one command string.
[root@localhost ~]# ysqlsh -h -U yugabyte -c "\d t; \x; SELECT * FROM t;"
Table "public.t"
Column | Type | Collation | Nullable | Default
--------+-------------------+-----------+----------+---------
c1 | integer | | not null |
c2 | character varying | | |
Indexes:
"t_pkey" PRIMARY KEY, lsm (c1 HASH)
Note that only the first meta-command was executed.
One option to get around this limitation is to pipe the command string into ysqlsh, using the \\ meta-command separator.
Example:
[root@localhost ~]# echo '\d t \\ \x \\ SELECT * FROM t;' | ysqlsh -U yugabyte
Table "public.t"
Column | Type | Collation | Nullable | Default
--------+-------------------+-----------+----------+---------
c1 | integer | | not null |
c2 | character varying | | |
Indexes:
"t_pkey" PRIMARY KEY, lsm (c1 HASH)
Expanded display is on.
-[ RECORD 1 ]
c1 | 1
c2 | A
-[ RECORD 2 ]
c1 | 2
c2 | B
-[ RECORD 3 ]
c1 | 3
c2 | C
The other option is use multiple -c flags, passing in each command separately.
Example:
[root@localhost ~]# ysqlsh -U yugabyte -c "\d t;" -c "\x" -c "SELECT * FROM t;"
Table "public.t"
Column | Type | Collation | Nullable | Default
--------+-------------------+-----------+----------+---------
c1 | integer | | not null |
c2 | character varying | | |
Indexes:
"t_pkey" PRIMARY KEY, lsm (c1 HASH)
Expanded display is on.
-[ RECORD 1 ]
c1 | 1
c2 | A
-[ RECORD 2 ]
c1 | 2
c2 | B
-[ RECORD 3 ]
c1 | 3
c2 | C
Have Fun!
