![]() ![]() The rest of the database options for the read and write connections will be merged from the main mysql configuration array. The read and write keys have array values containing a single key: host. Note that three keys have been added to the configuration array: read, write and sticky. After the database has been created, you may easily configure your environment variables to point to this database by placing the absolute path to the database in the DB_DATABASE environment variable: ![]() You can create a new SQLite database using the touch command in your terminal: touch database/database.sqlite. SQLite databases are contained within a single file on your filesystem. However, you are free to modify your database configuration as needed for your local database. Examples for most of Laravel's supported database systems are provided in this file.īy default, Laravel's sample environment configuration is ready to use with Laravel Sail, which is a Docker configuration for developing Laravel applications on your local machine. Most of the configuration options within this file are driven by the values of your application's environment variables. In this file, you may define all of your database connections, as well as specify which connection should be used by default. The configuration for Laravel's database services is located in your application's config/database.php configuration file. USER_VARIABLES ORDER BY VARIABLE_NAME Empty set ( 0. USER_VARIABLES ORDER BY VARIABLE_NAME + -+-+-+-+ | VARIABLE_NAME | VARIABLE_VALUE | VARIABLE_TYPE | CHARACTER_SET_NAME | + -+-+-+-+ | str | 123 | VARCHAR | utf8mb3 | + -+-+-+-+ FLUSH USER_VARIABLES SELECT * FROM information_schema. SET str = CAST ( 123 AS CHAR ( 5 )) SELECT * FROM information_schema. User-defined variables are reset and the Information Schema table emptied with the FLUSH USER_VARIABLES statement. User-defined variables can be viewed in the Information Schema USER_VARIABLES Table (as part of the User Variables plugin) from MariaDB 10.2. SELECT a, b, c, AS counter FROM my_table They must be used to PREPARE a prepared statement: = 'DELETE FROM my_table WHERE c>1 ' Īnother common use is to include a counter in a query: SET = 0 However there are some exceptions, like the LIMIT clause. ![]() User-defined variables can be used in most MariaDB's statements and clauses which accept an SQL expression. It is unsafe to read a user-defined variable and set its value in the same statement (unless the command is SET), because the order of these actions is undefined. If a variable has not been used yet, its value is NULL: SELECT x IS NULL + -+ | x IS NULL | + -+ | 1 | + -+ Since user-defined variables type cannot be declared, the only way to force their type is using CAST() or CONVERT(): SET str = CAST ( 123 AS CHAR ( 5 )) To set a value for a user-defined variable you can use: They can be read even if no value has been set yet in that case, they are NULL. ![]() User-defined variables cannot be declared. User-variables names are case insensitive, though they were case sensitive in MySQL 4.1 and older versions. If other characters are used, the name can be quoted in one of the following ways: User-defined variables names must be preceded by a single at character ( While it is safe to use a reserved word as a user-variable name, the only allowed characters are ASCII letters, digits, dollar sign ( $), underscore ( _) and dot (. However, these variables can be shared between several queries and stored programs. This means that no one can access user-defined variables that have been set by another user, and when the session is closed these variables expire. User-defined variables are variables which can be created by the user and exist in the session. ![]()
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