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External key to MySQL

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jonetta last edited by

The outer key in MySQL, in the idea, adds a line from one table to another if the second one matches the external key?
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Alberto last edited by

Well, that's the way the questions are formulated to make them understand yourself. "When the fire burns, it's in the bay," it's called readers, each in its own way. All I've learned is that the question sounds outside. I answer as I can.
The outer key is a reference to the parent: each of the occupants of the house points to the house where he lives; and the house not only knows nothing about his tenants, it doesn't even suspect that they exist. The external key is a duplicate of the primary key, a unique set of values of the fields (fields) of the parent table. Maintains data integrity and relationship between nature (tables)
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Error: ORA-01652: It is not possible to increase the interim segment to 8192 in USERS
Software Programming • sql oracle sqldeveloper • • Raziyah00

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First thing you want to see if there's any more room on the CD:C:\> dir e:|find "bytes free" 10 Dir(s) 99.138.351.104 bytes free or more detailed as the Administrator:C:\WINDOWS\system32> fsutil volume diskfree е: Total free bytes : 99.138.351.104 ( 92,3 GB) Total bytes : 137.438.949.376 (128,0 GB) Total quota free bytes : 99.138.351.104 ( 92,3 GB) In the evaluation, consider that each data file can reach a max. 32G.In addition, if the team is moved by a spider,alter tablespace users add datafile E:\ORACLE\ORACLE10\DATABASE\new_segment_26062021_2.dbf' ----^ size 10m autoextend on maxsize unlimited; There's no opening. The new file has not been created.
the mysql query browser or mysql workbench are SGBD?
Software Programming • database • • inna

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MySQL Server is a Database Management System (SGBD). Workbench is a visual tool for controlling server functionality. Workbench will only work if MySQL Server is properly installed. The same goes for Query Browser.
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Place limit in relation one to many php laravel
Software Programming • php mysql sql laravel • • Duquan

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That type of restrictions is better to work on the logical section of the application, which reduces the amount of queries to your database. You can make a simple validation with the function count() de Laravel:public function store($article) { $user = auth()->user(); // un usuario, el logueado por ejm if ($user->articles->count() >= 5) { // condición return 'Lo sentimos, has alcanzado el máximo permitido (5)' // mensaje } else { // la lógica de tu operación.. }
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<select> that displays all keys of a table in PHP does not return the keys</select>
Software Programming • php • • Pearlaqua

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Fake to perform $seleciona_nomes->execute();$seleciona_nomes = $conexao->query("SELECT cd_itens_venda FROM itens_venda"); $seleciona_nomes->execute(); .......... missed showing the option text<option value="VALOR A PASSAR">TEXTO MOSTRADO</option> _echo "<option value='{$valor['cd_itens_venda']}'>'{$valor['cd_itens_venda']}'</option>";
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Duplicate entry for key primary mysql Error MySQL PHP
Software Programming • php mysql sql csv • • rielyn

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For this case, you can use the modifier IGNORE in your SQL sentence.For example:$sql="INSERT IGNORE INTO `articulos_csv` (`ean`) VALUES ('$arrayDigitosFinal');"; I leave you here what the https://dev.mysql.com/doc/refman/8.0/en/insert.html about this modifier:If you use the IGNORE modifier, ignoreable errors that occur while executing the INSERT statement are ignored. For example, without IGNORE, a row that duplicates an existing UNIQUE index or PRIMARY KEY value in the table causes a duplicate-key error and the statement is aborted. With IGNORE, the row is discarded and no error occurs. Ignored errors generate warnings instead.IGNORE has a similar effect on inserts into partitioned tables where no partition matching a given value is found. Without IGNORE, such INSERT statements are aborted with an error. When INSERT IGNORE is used, the insert operation fails silently for rows containing the unmatched value, but inserts rows that are matched. For an example, see Section 23.2.2, “LIST Partitioning”.Data conversions that would trigger errors abort the statement if IGNORE is not specified. With IGNORE, invalid values are adjusted to the closest values and inserted; warnings are produced but the statement does not abort. You can determine with the mysql_info() C API function how many rows were actually inserted into the table.If you use the modifier IGNORE, ignore the ignoble mistakes that occurs when the instruction is executed INSERT. For example, without IGNORE, a row that duplicates an index UNIQUE existing or value in the table causes a duplicate key error and the declaration is aborted. With IGNORE, the row is discarded and not produces no mistake. Instead, the mistakes ignored generate Warnings.IGNORE has a similar effect on the inserts in tables partitions where there is no partition that matches a given value. No IGNOREsuch instructions INSERT canceled with a mistake. When used INSERT IGNOREthe insertion operation silently fails for rows containing the value not matching, but inserting matching rows. To see an example, consult https://dev.mysql.com/doc/refman/8.0/en/partitioning-list.html .Data conversions that would trigger errors abort declaration if not specified IGNORE. With IGNORE, values not are adjusted to the nearest values and are inserted; produce warnings but the statement is not canceled. Maybe determine with the function of the C API https://dev.mysql.com/doc/c-api/8.0/en/mysql-info.html How many rows were actually inserted into the table.For more information, see the effect of IGNORE in the implementation of instructions.PostdataIn the final link you will see what effect the use of IGNORE and decide when to use this modifier and when not. For example, I wouldn't use it in massive insertions where I'm interested in having more or less controlled the sequence of an incremental auto column in the table, because its use does not prevent the sequence from increasing in the face of failed attempts. In that case, I would verify the existence of the registry before inserting it.
Is it right to add the key to the dictionary? How do you put the keys in the line?
Software Programming • python dict • • carriann

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if input_number not in directories: directories[input_number] = [] - these things usually go through. collections.defaultdict(list)♪ From defaultdict, you don't need to add new "films" - they'll be created automatically on the record.Get all the keys out justprint(",".join(directories.keys()))
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Need to backup remote database using mysqldump
SQL, Database Testing • mysql • • charlenef

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Unfortunately, you cant continue your failed backup. When mysqldump returns a failed status you have to start over again. My first recommendation is to compress your script before transmitting it mysqldump -h 192.168.10.209 -u user -ppassword testdb | gzip > dump.sql.gz Another recommendation is to connect to the remote server via ssh, then make the backup in the remote server (never will fail for network issues because is a local backup) and, in the last step you could transmit the file (after compress of course). Other than that, the other 2 options more used are PERCONA XTRA BACKUP and MYSQL ENTERPRISE BACKUP but there are also high prices involved.
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Registrations in MySQL are saved with line jumps
Software Programming • php mysql sql md5 • • Duquan

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Adapted response from this https://es.stackoverflow.com/questions/149433/registros-en-mysql-se-guardan-con-saltos-de-l%C3%ADnea#comment279847_149433 :fgets($file) return the row with the line jump included, if you do not want it in the database, remove it before making the insert. It would be something like:$linea = trim(preg_replace('/\s\s+/', ' ', $linea));
External grpc with private key and Go
Software Programming • server golang grpc test run • • briley

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First, we'll find out where we need to get involved, all the checks on the mistake I've put down.conn, err := grpc.Dial("127.0.0.1:1234") There is room for a gRPC client configuration with a ServerOptions. grpc.Dial("127.0.0.1:1234", grpc.WithInsecure(), grpc.WithBlock())But that's not all. We need to work through the protobath for this, we'll register our protobath. pb "google.golang.org/grpc/examples/helloworld/helloworld"c := pb.NewGreeterClient(conn) Now we can send the server that runs this protobath, a message.ctx, cancel := context.WithTimeout(context.Background(), time.Second) r, err := c.SayHello(ctx, &pb.HelloRequest{Name: name}) if err != nil { log.Fatalf("could not greet: %v", err) } log.Printf("Greeting: %s", r.GetMessage()) SayHello, HelloRequest, GetMessage implemented in the protobaf itself.You can read it in more detail. https://grpc.io/docs/languages/go/basics/ Examples of the code https://github.com/grpc/grpc-go/blob/master/examples/helloworld/greeter_client/main.go
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Need to optimize simple SELECT query for InnoDB table with 2million rows
SQL, Database Testing • mysql select optimization innodb myisam • • elysha

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First, what you need to focus on are the three fields in the query id created_at person_id The index you have (created_at,person_id) will make the query do an index scan across all the days of created_at after CURRENT_DATE looking for the person_id. SUGGESTION #1 : You will definitely need a different index MyISAM If login_events is MyISAM, this is the index you need ALTER TABLE login_events ADD INDEX person_date_ndx (person_id,created_at,id); This changes the query because the query will look for the specific person_id and scan all days for person_id 1 only. The reason id is included in the index ? The query will retrieve the id from the index only file rather than the table. That way, all 3 fields are retrieved from the index file instead of 2 fields from the index and 1 from the table. InnoDB If login_events is InnoDB, this is the index you need ALTER TABLE login_events ADD INDEX person_date_ndx (person_id,created_at); The reason I recommend this is the same, but you do not need to include id. Why? All index pages include an index point back to the clustered index so retrieval of an index will intrinsically access the row anyway, thus accessing id. Adding id to the index would simply be redundant. SUGGESTION #2 : Change the Date Comparison From the expression DATE(created_at) >= DATE(CURRENT_DATE) I can tell that created_at is either DATETIME or TIMESTAMP. The expression forces the query to convert every row's DATETIME value of created_on into a DATE. Therefore, instead of SELECT login_events.id FROM login_events WHERE ( DATE(created_at) >= DATE(CURRENT_DATE) AND person_id = 1 ) LIMIT 1 express the date comparison as a time comparison starting from midnight of today SELECT login_events.id FROM login_events WHERE ( created_at >= (DATE(NOW()) + INTERVAL 0 SECOND) AND person_id = 1 ) LIMIT 1 CAVEAT Since the table is so small, either storage engine would be fine. I would give the edge to MyISAM. Give it a Try !!!
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Can the outer key be the primary key at the same time? MySQL
Software Programming • mysql • • kalena

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Read the terms. The outer key is limitationwhich you put on the values of one field or several fields. DSB checks everything you're trying to record. Your values should be met among similar fields in another table.It helps to preserve the integrity of the base when you have several associated tables.At the same time, the field in another table should be a unique key. It's for productivity. You have to collect them on the index and point out that this index is unique, then the external key can be created.Now, if you have a table on which the foreign key is restricted. If the relationship between the tables one to onethese fields will obviously be unique.The primary key must be unique, too. Very often, the primary key is not the natural key, but the surrogate is the whole field in which the natural series 1, 2, 3, ... But you may not add a field that is only used as a surrogate key if you still have a field that is uniquely guaranteed.Thus, it is possible to take the fields in the table on which the limitation is imposed. external key and make a primary key out of them because the values in these fields are unique.Should we do that? Sometimes, yes, sometimes not. Usually, such a decision should give something to the programmer who supports the programme. In your example, I understand the programmer tried to say that every product in every purchase could meet once. But I wouldn't do that key because magazine It's an independent nature that should have its own, independent key.Another case is one to one or one. She often meets when you try to keep a little hierarchy of classes in several tables. In this case, the external key used as the primary key highlights the deep link between the tables. You're saying it's a big building where some parts may not be present. You put these parts in a few tables because it's so right in terms of the reflex method, but you're also pointing out that, somewhere above the level, these values will be collected in a single whole.In this case, the primary key of the field on which the restriction is placed is the outer key, a beautiful clue.
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Count records after obtaining results from a query
Software Programming • mysql sql base de datos • • simrah

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you are looking to make a group of the data, just that column. . select dias, count(dias) from tabla group by dias;
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Setting MySql External Access
Software Programming • mysql ubuntu • • Kadir

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To configure external access to your MySQL server you must follow the following steps:Make MySQL server listen to external connections (and not just from localhost, 127.0.0.1).Enable access to the MySQL server in the firewall.Create the user root remote and give him privileges.Then step to detail each of the steps.Make the MySQL server listen to external connectionsYou have to edit the file my.cnf to change bind-address a 0.0.0.0.In this particular case the file was located /etc/mysql/mysql.conf.d/mysqld.cnf.Enable access to the MySQL server in the firewallAs it was being used as firewall ufw, you have to activate the access to the 3306 port used by the MySQL server by typing:# ufw allow 3306 Create the user root and give him privilegesTo create a user root the following SQL queries should be used:CREATE USER 'root'@'%' IDENTIFIED BY 'tu_clave_de_root'; GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'tu_clave_de_root'; If the user 'root'@'%' already exists, but the password is unknown, you can change using:ALTER USER 'root'@'%' IDENTIFIED BY 'tu_clave_de_root';
Hibernate, external key to two tables
Software Programming • sql postgresql hibernate • • inna

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You don't need an external key to the two tables, you need to make a survey of the tables where there will be a basic substance with a set of common fields and heirs that will refer to the basic essence through foreign key and then an additional table in your case will refer to the base table.Example.create table person ( id integer not null constraint person_pk primary key ); create table buyer ( id integer not null constraint buyer_pkey primary key constraint buyer_person_id_fk references person ); create table seller ( id integer not null constraint seller_pk primary key constraint seller_person_id_fk references person ); create table account ( id integer not null constraint account_pk primary key, person_id integer not null references person ); I advise you to read about the annotation of @Inheritance in hibernate, it will allow you to run tables at levels orm.
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create and relate 2 temporary tables
Software Programming • mysql base de datos • • Raziyah00

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The mistake is for this line of yours:foreign key(idpregunta)references PREGUNTAS(idpregunta) Try:CREATE temporary table OPCION ( idopcion int auto_increment, primary key(idopcion), idpregunta int, opcion varchar(50), valor int, foreign key(idpregunta) references PREGUNTAS(idpregunta) ); Greetings.

External key to MySQL

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