How to convert a set of 4 rows to columns in MySQL? -

-

i have mysql question, , have no idea how resolve it.

i have following query:

select p.nombre, ti.tallerhorario_id persona p, talleresinscritos ti p.pasaporte = ti.pasaporte

at result this:

enter image description here

i'm looking make query in second column doesn't show row every "tallerhorario_id", every "nombre".

for example:

euclides | 7 | 24 | 32 | 48

liz lorena | 4 | 18 | 33 | 47

every person have 4 rows associated, without exceptions.

could me please?

thank you!

the simplest method put values in 1 column, using group_concat():

select p.nombre, group_concat(ti.tallerhorario_id) persona p join -- learn use proper explicit join syntax      talleresinscritos ti       on p.pasaporte = ti.pasaporte group p.nombre;

a comma-delimited list not asked for, might solve problem. if have counter, 1, 2, 3, , 4, second table, can using conditional aggregation:

select p.nombre,         max(case when counter = 1 ti.tallerhorario_id end) id1,        max(case when counter = 2 ti.tallerhorario_id end) id2,        max(case when counter = 3 ti.tallerhorario_id end) id3,        max(case when counter = 4 ti.tallerhorario_id end) id4 persona p join -- learn use proper explicit join syntax      talleresinscritos ti       on p.pasaporte = ti.pasaporte group p.nombre;

finally, if don't have counter, 1 way add 1 uses variables:

select p.nombre,         max(case when counter = 1 ti.tallerhorario_id end) id1,        max(case when counter = 2 ti.tallerhorario_id end) id2,        max(case when counter = 3 ti.tallerhorario_id end) id3,        max(case when counter = 4 ti.tallerhorario_id end) id4 persona p join -- learn use proper explicit join syntax      (select ti.*,              (@rn := if(@p = pasaporte, @rn + 1                         if(@p := pasaporte, 1, 1)                        )              ) counter       talleresinscritos ti cross join            (select @p := '', @rn := 0) params       order ti.pasaporte      ) ti      on p.pasaporte = ti.pasaporte group p.nombre;

Comments

Post a Comment

Popular posts from this blog

PHP DOM loadHTML() method unusual warning -

-
i had following code works fine on localhost: $document = new domdocument(); $document->loadhtml($p_result); $form = $document->getelementsbytagname('form')->item(0); // code continues using $form variable after same code updated on outside server, loadhtml() failed , issued warning. warning: domdocument::loadhtml() expects parameter 1 valid path, string given in path/name/to/script.php returned null instead of object code pretty gets fatal error. note contents of $p_result absolutely same on outside server , on localhost. but why displays kind of warning , why not work? doesn't loadhtml() expects argument 1 string in first place? why method expects parameter 1 valid path ? just make clear i'm not calling loadhtmlfile() , i'm calling loadhtml() . thanks. you're affected one of php bugs . issue present in php 5.6.8 , 5.6.9. have affected php version on server, , bug-free version on localhost. the bug forbids null
Read more

python - How to create jsonb index using GIN on SQLAlchemy? -

-
here's current code creating index jsonb. index("mytable_data_idx_id_key", mytable.data['id'].astext, postgresql_using='gin') but got error. sqlalchemy.exc.programmingerror: (psycopg2.programmingerror) data type text has no default operator class access method "gin" hint: must specify operator class index or define default operator class data type. [sql: "create index event_data_idx_id_key on event using gin ((data ->> 'id'))"] is there way create index on sqlalchemy? the postgresql specific sqlalchemy docs @ http://docs.sqlalchemy.org/en/latest/dialects/postgresql.html#operator-classes mention postgresql_ops dictionary provide "operator class" used postgresql, , provide example illustrating use: index('my_index', my_table.c.id, my_table.c.data, postgresql_ops={ 'data': 'text_pattern_ops',
Read more

c# - TransactionScope not rolling back although no complete() is called -

-
i'm using transactionscope rollback transaction fail bool errorreported = false; action<importerrorlog> newerrorcallback = e => { errorreported = true; errorcallback(e); }; using (var transaction = new transactionscope()) { foreach (importtaskdefinition task in taskdefinition) { loader.load(streamfile, newerrorcallback, task.destinationtable, processingtaskid); } if (!errorreported) transaction.complete(); } i'm sure there no transactionscope started ahead or after code. i'm using entity framework insert in db. regardless state of errorreported transaction never rolled in case of error. what missing ? transactionscope sets transaction.current . that's does. wants transacted must @ property. i believe ef each time connection opened reason. probably, connection open when scope installed. open connection inside of scope or enlist manually. ef has nasty "design decision": default opens
Read more