MySQL Join does not return data that matches in both tables in a new database instance

I’ve been hiding here for several months now and am learning a lot from reading other questions, but this is the first time I have been brave enough to ask him!

SELECT  * FROM tableA a
JOIN tableB b ON b.tableBid = a.tableBid
WHERE a.tableAcol = 'paramValue';

I only have 39 rows in table B, and for each of them there is a row in tableA for paramValue with a suitable tableBid, so I expect to get 39 rows back. And indeed, in another instance of the database, I do.

I do not see significant differences in the instances, although this may be ignorance, but in this new instance I get only 7 records with the same request.

If I changed the request to

SELECT  * FROM tableA a
LEFT JOIN tableB b ON b.tableBid = a.tableBid
WHERE a.tableAcol = 'paramValue';

or

SELECT  * FROM tableA a
LEFT JOIN tableB b ON a.tableBid = b.tableBid
WHERE a.tableAcol = 'paramValue';

then I get 39 rows that I expect using matching a.tableBid b.tableBid in all cases and no zeros

. - , .

,

 CREATE TABLE tableB (  
tableBid varchar(30) NOT NULL   PRIMARY KEY,
nameB varchar(25) NOT NULL  ,
description varchar(40) NOT NULL);

CREATE TABLE tableA (
userID varchar(30) NOT NULL,
tableBid Varchar(30) NOT NULL,
info varchar(10) NOT NULL,
PRIMARY KEY(userID, tableBID));

insert into tableB (tableBid, nameB, description)
values 
('a', 'a name', 'blah'),
('b', 'b name', 'blah'),
('c', 'c name', 'blah'),
('d', 'd name', 'blah');

insert into tableA (userID, tableBid, info)
values
('deel','a',  'blah'),
('deel','b',  'blah'),
('deel','c',  'blah'),
('deel','d',  'blah');

SELECT  * FROM tableA a
LEFT JOIN tableB b ON b.tableBid = a.tableBid
WHERE a.userID = 'deel';

4 :

deel    a   blah    a   a name  blah
deel    b   blah    b   b name  blah
deel    c   blah    c   c name  blah
deel    d   blah    d   d name  blah

SELECT  * FROM tableA a
JOIN tableB b ON b.tableBid = a.tableBid
WHERE a.userID = 'deel';

deel    d   blah    d   d name  blah

SHOW CREATE TABLE tableA

CREATE TABLE tablea (  userID varchar (30) NOT NULL,  tableBid varchar (30) NOT NULL,  info varchar (10) NOT NULL,   (userID, tableBid)  ) ENGINE = Xeround DEFAULT CHARSET = latin1

SHOW CREATE TABLE tableB

tableb (  tableBid varchar (30) NOT NULL,  nameB varchar (25) NOT NULL,  description varchar (40) NOT NULL,   (tableBid)  ) ENGINE = Xeround DEFAULT CHARSET = latin1