![]() ![]() You can also chain withKeyName() to override default key name that is generated from table and column names (result is identical to specifying second parameter to function foreign()).ĭeferrable foreign constraint is supported on Postgres and Oracle and can be set by chaining. You can also chain onDelete() and/or onUpdate() to set the reference option (RESTRICT, CASCADE, SET NULL, NO ACTION) for the operation. Table.foreign(columns, )Īdds a foreign key constraint to a table for an existing column using table.foreign(column).references(column) or multiple columns using table.foreign(columns).references(columns).inTable(table).Ī default key name using the columns is used unless foreignKeyName is specified. If you want to chain unique() while creating new column you can use unique foreign # In PostgreSQL, SQLite and MSSQL a partial unique index can be specified by setting a 'where' predicate. In MSSQL and Postgres, you can set the useConstraint option to true to create a unique constraint instead of a unique index (defaults to false for MSSQL, true for Postgres without predicate, false for Postgres with predicate). Deferrable unique constraint are supported on Postgres and Oracle and can be set by passing deferrable option to options object. If you need to create a composite index, pass an array of column to columns. dump command inside the sqlite3 prompt to export your SQLite database as an SQL file, you can restore the state of the database by feeding the SQL file back into sqlite3 using the. A default index name using the columns is used unless indexName is specified. exit Importing data from SQL files After having used the. In MySQL, the storage engine index type may be 'btree' or 'hash' index types, more info in Index Options section. ![]() Table.increments(name, options=)Īdds an unique index to a table over the given columns. To find out the structure of a table via the SQLite command-line shell program, you follow these steps: First, connect to a database via the SQLite command-line shell program: sqlite3 c:\sqlite\db\chinook.db Code language: SQL (Structured Query Language) (sql) Then, issue the following command. Renames a column from one name to another. dropSchemaIfExists ( 'public', true ) Schema Building # dropColumn #ĭrops a column, specified by the column's name dropColumns #ĭrops multiple columns, taking a variable number of column names. dropSchemaIfExists ( 'public' ) //drop schema if exists 'public' cascade Unfortunately pragma statements do not work with parameters you'll have to manually insert the table name (make sure it's not sourced from an untrusted source and escape it properly).Knex. > for row in conn.execute("pragma table_info('sqlite_master')").fetchall(): Database documentation is a set of descriptions of the data. with descriptions) of schema of your databases. This command works just fine from python: > import sqlite3 List of tools that allow the documentation (e.g. The schema.sql file is the target file that will. Columns in the result set include the column name, data type, whether or not the column can be NULL, and the default value for the column. schema component is the command that tells SQLite to export the database schema without any accompanying data. ![]() This pragma returns one row for each column in the named table. To get column names for a given table, use the pragma table_info command: So to get a list of all table names execute: SELECT name FROM sqlite_master ![]() The SQLITE_MASTER table looks like this: CREATE TABLE sqlite_master ( Every SQLite database has an SQLITE_MASTER table that defines the schema for the database. From within a C/C program (or a script using Tcl/Ruby/Perl/Python bindings) you can get access to table and index names by doing a SELECT on a special table named "SQLITE_MASTER". ![]()
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