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Deleting all rows from a table can be very time-consuming. Some DBMS [clarification needed] offer a TRUNCATE TABLE command that works a lot quicker, as it only alters metadata and typically does not spend time enforcing constraints or firing triggers. DELETE only deletes the rows. For deleting a table entirely the DROP command can be used.
In SQL, the data manipulation language comprises the SQL-data change statements, [3] which modify stored data but not the schema or database objects. Manipulation of persistent database objects, e.g., tables or stored procedures, via the SQL schema statements, [3] rather than the data stored within them, is considered to be part of a separate data definition language (DDL).
The detailed semantics of "the" ternary operator as well as its syntax differs significantly from language to language. A top level distinction from one language to another is whether the expressions permit side effects (as in most procedural languages) and whether the language provides short-circuit evaluation semantics, whereby only the selected expression is evaluated (most standard ...
Row labels are used to apply a filter to one or more rows that have to be shown in the pivot table. For instance, if the "Salesperson" field is dragged on this area then the other output table constructed will have values from the column "Salesperson", i.e., one will have a number of rows equal to the number of "Sales Person". There will also ...
Triggers are fully supported and can be attached to tables. Triggers can be per-column and conditional, in that UPDATE triggers can target specific columns of a table, and triggers can be told to execute under a set of conditions as specified in the trigger's WHERE clause. Triggers can be attached to views by using the INSTEAD OF condition ...
Database commands can be issued as above, in Lasso's db-independent metalanguage, in which case the same search code works for MySQL, FileMaker Pro or for any other database backend with which Lasso can connect. If needed, a SQL statement can of course be embedded in the inline when using a database server that supports SQL:
In modern languages, a line comment starts with a delimiter but some older languages designate a column at which subsequent text is considered comment. [7] Many languages support both block and line comments – using different delimiters for each.
This implementation uses a pointer to the first element in the list as a surrogate for the entire list. If a new value is added to the beginning of the list, head has to be changed to point to the new element. Since C arguments are always passed by value, using double indirection allows the insertion to be implemented correctly, and has the ...