FAQ:

Why?

Because it's a Tuesday night in South Dakota?

Should I actually use this?

Probably not.

Why isn't this ANSI SQL?

Because supporting parsing actual SQL in bash is beyond the scope of a couple hour project (for me).

Supported SQL(ish) Syntax:

SELECT

'SELECT' column_expr[, column_expr...]
['FROM' table_name]
['WHERE' bool_expression]
['GROUPBY' column_expr] ';'

INSERT

'INSERT' ['INTO'] table_name
'(' column_expr[, column_expr...] ')'
'VALUES '(' value_expr[, value_expr...] ')';

UPDATE

'UPDATE' table_name SET
column_name '=' value_expr[, column_name '=' value_expr]
['WHERE' bool_expr] ';'

DELETE

'DELETE FROM' table_name
['WHERE' bool_expr] ';'

table_name := identifier

column_name := identifier

column_expr := column_name | value_expr

value_expr := '"' value_text '"'

value_text :~ ([^"]|\|")*

bool_expr := value_expr equal_op value_expr [(AND | OR) bool_expr]

equal_op := = | < | > | <= | >= | <>

identifier :~ [A-Za-z0-9_]+