Table Creation, Modification and Deletion

KX SQL supports the Data Definition Language (DDL) which can be used to handle the database descriptions and schemas. It can also be used to define and modify the structure of the data.

Create

CREATE can be used to create a new table in kdb Insights Core in memory.

Examples

Creating an empty table of 2 columns, using varchar and float to define columns of q type symbol and float respectively:
```
s)CREATE TABLE tripsFare (vendor varchar,fare float)
s.e.SELECT * FROM tripsFare
```

Creating an empty table of 10 columns, using a number of different data types:

s)CREATE TABLE cars (id int, Name varchar(250), "Miles_per_Gallon" smallint, "Cylinders" smallint, "Displacement" smallint, "Horsepower" smallint, "Weight_in_lbs" smallint NOT NULL, "Acceleration" smallint, "Year" date NOT NULL, "Origin" character varchar(60));
s.e.SELECT * FROM cars

Note

We could also have used char(n>1) here. If we wanted to define a column of q type char - we would use char(1).

See here for a full list of supported data types.

Insert

INSERT can be used to add new records to a table in memory.

Examples

Adding one row:

s)INSERT INTO tripsFare(vendor,fare) values ('CMT',100)
s)SELECT * FROM tripsFare

- Creating a table and adding a row:

s)INSERT INTO tripsFare(vendor,fare) values ('DDS',301),('CMT',589)
s)SELECT * FROM tripsFare

Creating a table and adding two rows:

s)CREATE TABLE cars (id int, Name varchar(250), "Miles_per_Gallon" smallint, "Cylinders" smallint, "Displacement" smallint, "Horsepower" smallint, "Weight_in_lbs" smallint NOT NULL, "Acceleration" smallint, "Year" date NOT NULL, "Origin" character varchar(60));
s)INSERT INTO cars VALUES (1, 'chevrolet chevelle malibu', 18, 8, 307, 130, 3504, 12, '1970-01-01', 'USA');
s)INSERT INTO cars VALUES (2, 'volkswagen 1131 deluxe sedan', 26, 4, 97, 46, 1835, 21, '1970-01-01', 'Europe');

Drop

DROP can be used to delete a kdb Insights Core table from memory.

Examples

Dropping a table:
```
s)DROP table IF EXISTS tripsFare
```