Expression syntax

expr:
expr AND expr
 expr && expr
 expr OR expr
 expr  expr
 expr XOR expr
 NOT expr
 bool_pri IS BOOL_VALUE
 bool_pri IS not BOOL_VALUE
 bool_pri IS UNKNOWN
 bool_pri IS not UNKNOWN
 bool_pri := expr
;

bool_pri:
bool_pri IS NULL
 bool_pri IS not NULL
 bool_pri COMP_LE predicate
 bool_pri COMP_LE sub_query_flag '(' select_no_parens ')'
 bool_pri COMP_LT predicate
 bool_pri COMP_LT sub_query_flag '(' select_no_parens ')'
 bool_pri COMP_EQ predicate
 bool_pri COMP_EQ sub_query_flag '(' select_no_parens ')'
 bool_pri COMP_NSEQ predicate
 bool_pri COMP_GE predicate
 bool_pri COMP_GE sub_query_flag '(' select_no_parens ')'
 bool_pri COMP_GT predicate
 bool_pri COMP_GT sub_query_flag '(' select_no_parens ')
 bool_pri COMP_NE predicate
 bool_pri COMP_NE sub_query_flag '(' select_no_parens ')'
 predicate 
;

comparison_operator:
COMP_LE ==> '<='
COMP_LT ==> '<'
COMP_EQ ==> '='
COMP_NSEQ ==> '<=>'
COMP_GE ==> '>='
COMP_GT ==> '>'
COMP_NE ==> '!='

predicate:
bit_expr IN in_expr
 bit_expr not IN in_expr
 bit_expr not BETWEEN bit_expr AND predicate
 bit_expr BETWEEN bit_expr AND predicate
 bit_expr LIKE simple_expr
 bit_expr LIKE simple_expr ESCAPE simple_expr
 bit_expr not LIKE simple_expr
 bit_expr not LIKE simple_expr ESCAPE simple_expr
 bit_expr REGEXP bit_expr
 bit_expr not REGEXP bit_expr
 bit_expr
;

bit_expr:
bit_expr '' bit_expr 
 bit_expr '&' bit_expr
 bit_expr << bit_expr 
 bit_expr >> bit_expr
 bit_expr '+' bit_expr
 bit_expr '-' bit_expr
 bit_expr '+' INTERVAL expr date_unit
 bit_expr '-' INTERVAL expr date_unit
 bit_expr '*' bit_expr 
 bit_expr '/' bit_expr
 bit_expr '%' bit_expr
 bit_expr MOD bit_expr
 bit_expr DIV bit_expr
 bit_expr '^' bit_expr
 simple_expr
;

simple_expr:
simple_expr collation
 BINARY simple_expr
 column_ref
 expr_const
 simple_expr CNNOP simple_expr
 '+' simple_expr 
 '-' simple_expr
 '~' simple_expr
 '!' simple_expr
 not simple_expr
 select_with_parens
 '(' expr ')'
 '(' expr_list ',' expr ')'
 ROW '(' expr_list ',' expr ')'
 EXISTS select_with_parens
 MATCH '(' column_list ')' AGAINST '(' STRING_VALUE opt_mode_flag ')'
 case_expr
 func_expr
 window_function
 USER_VARIABLE
;