* [TD-5398]<fix>: taosdemo 4096 columns table creation failed.

* change column name prefix from col to c for maxium column number to fix buffer length.

* use accurate buffer length.

* fix test case for column name be shorter.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* cherry pick from develop branch.

* [TD-5136]<feature>: taosdemo simulate real senario.

* update test case according to taosdemo change

* adjust range of semi-random data.

* [TD-3906]<fix>: taosdemo back to 4 INT columns.

* [TD-3906]<fix>: taosdemo back to 4 columns.

test case need change correspondingly.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* [TD-3607] <fix>: fix taosdemo buffer overflow.

* [TD-3607] <fix>: taosdemo buffer overflow.

add tmp buffer.

* [TD-3607] <fix>: taosdemo buffer overflow.

fix data generation.

* [TD-3607] <fix>: taosdemo buffer overflow.

fix normal table writting.

* [TD-3607] <fix>: taosdemo buffer overflow.

remove tail spaces.

* [TD-3607] <fix>: taosdemo buffer overflow.

fix taosdemo alter table test case.

* [TD-3607] <fix>: taosdemo buffer overflow.

fix taosdemo alter table case.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* [TD-3197] <fix>: fix taosdemo coverity scan issues.

* [TD-3197] <fix>: fix taosdemo coverity scan issue.

fix subscribeTest pids uninitialized.

* [TD-3197] <fix>: fix taosdemo coverity scan issues.

* [TD-3197] <fix>: fix coverity scan issues.

check super tbl info pointer.

* [TD-3197] <fix>: fix coverity scan issues.

move sub tbl query thread join into loop

* [TD-3197] <fix>: fix coverity scan issues.

remove unused variable

* [TD-3197] <fix>: fix coverity scan issues.

use more secure random library

* [TD-3197] <fix>: fix coverity scan issues.

use strncpy for more safe

* [TD-3197] <fix>: fix taosdemo coverity scan issue.

replace arc4random with rand().

* [TD-3197] <fix>: fix coverity scan issues.

check stb info pointer for start time

* [TD-3197] <fix>: fix coverity scan issues.

fix strcpy vulnerability

* [TD-3197] <fix>: fix taosdemo coverity scan issue.

modify taosdemoTest2. try to check database continously.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

Co-authored-by: NShuduo Sang <sdsang@taosdata.com>