func MoveSeparableExpressionToDataSource(dataSource planner.DataSource, joiner planner.Joiner, sep parser.Expression, rest parser.Expression) bool {
newFilterExpression := sep
// get the existing filter (if any)
filterExpression := dataSource.GetFilter()
if filterExpression != nil {
// build an AND expression with sep and the existing
newFilterExpression = parser.NewAndExpression(sep, filterExpression)
}
err := dataSource.SetFilter(newFilterExpression)
if err != nil {
// this data source doesn't support this filter
// continue once this becomes a loop
//log.Printf("Datasource rejected the new filter expression, %v", err)
return false
} else {
// it accepted the filter, now we just updated the join condition
err := joiner.SetCondition(rest)
if err != nil {
// hmmn, now joiner rejected its new condition
// we must back out the other change
//log.Printf("Datasource accepted, but now joiner rejected new filter expression, trying to reset")
err := dataSource.SetFilter(filterExpression)
if err != nil {
log.Fatalf("Datasource rejected setting its filter back to the original value, I don't know what to do")
}
return false
}
}
return true
}
func LookForSeparableExpression(expr parser.Expression) (parser.Expression, parser.Expression) {
count := NumberOfDataSourcesReferencedInExpression(expr)
if count < 2 {
// all symbols in this expression refer to the same datasource
// it could be moved out
return expr, nil
} else {
// this expression refers to symbols in 2 or more datasources
// it cannot be moved itself, but we may have to consier sub-expressions
and_expr, ok := expr.(*parser.AndExpression)
if ok {
// this expression is an AND expression so we can consider moving out
// its pieces
sep, remaining := LookForSeparableExpression(and_expr.Left)
if sep != nil {
// we found someting to remove
if remaining == nil {
// nothing remaining, return RHS
return sep, and_expr.Right
} else {
// build a new AND expression with the remaining piece and the RHS
return sep, parser.NewAndExpression(remaining, and_expr.Right)
}
} else {
// didn't find anything to remove, try the RHS
sep, remaining := LookForSeparableExpression(and_expr.Right)
if sep != nil {
// we found someting to remove
if remaining == nil {
// nothing left, return LHS
return sep, and_expr.Left
} else {
// build a new AND expression with the remaining piece and the RHS
return sep, parser.NewAndExpression(and_expr.Left, remaining)
}
}
}
}
}
// not an AND expression, nothing more we can do
return nil, nil
}
var oneSymbolExpressions = []parser.Expression{
parser.NewProperty("bob"),
parser.NewArrayLiteral(parser.ExpressionList{parser.NewProperty("bob")}),
parser.NewObjectLiteral(parser.Object{"field": parser.NewProperty("bob")}),
parser.NewNotExpression(parser.NewProperty("bob")),
parser.NewBracketMemberExpression(parser.NewProperty("bob"), parser.NewIntegerLiteral(0)),
}
var twoSymbolExpressions = []parser.Expression{
parser.NewPlusExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewMinusExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewMultiplyExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewDivideExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewOrExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewAndExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewLessThanExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewLessThanOrEqualExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewGreaterThanExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewGreaterThanOrEqualExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewEqualsExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
parser.NewNotEqualsExpression(parser.NewProperty("bob"), parser.NewProperty("jay")),
}
var threeSymbolExpressions = []parser.Expression{
parser.NewTernaryExpression(parser.NewProperty("bob"), parser.NewProperty("jay"), parser.NewProperty("cat")),
}
func TestSymbolsReferenced(t *testing.T) {
for _, v := range zeroSymbolExpressions {
func yyParse(yylex yyLexer) int {
var yyn int
var yylval yySymType
var yyVAL yySymType
yyS := make([]yySymType, yyMaxDepth)
Nerrs := 0 /* number of errors */
Errflag := 0 /* error recovery flag */
yystate := 0
yychar := -1
yyp := -1
goto yystack
ret0:
return 0
ret1:
return 1
yystack:
/* put a state and value onto the stack */
if yyDebug >= 4 {
fmt.Printf("char %v in %v\n", yyTokname(yychar), yyStatname(yystate))
}
yyp++
if yyp >= len(yyS) {
nyys := make([]yySymType, len(yyS)*2)
copy(nyys, yyS)
yyS = nyys
}
yyS[yyp] = yyVAL
yyS[yyp].yys = yystate
yynewstate:
yyn = yyPact[yystate]
if yyn <= yyFlag {
goto yydefault /* simple state */
}
if yychar < 0 {
yychar = yylex1(yylex, &yylval)
}
yyn += yychar
if yyn < 0 || yyn >= yyLast {
goto yydefault
}
yyn = yyAct[yyn]
if yyChk[yyn] == yychar { /* valid shift */
yychar = -1
yyVAL = yylval
yystate = yyn
if Errflag > 0 {
Errflag--
}
goto yystack
}
yydefault:
/* default state action */
yyn = yyDef[yystate]
if yyn == -2 {
if yychar < 0 {
yychar = yylex1(yylex, &yylval)
}
/* look through exception table */
xi := 0
for {
if yyExca[xi+0] == -1 && yyExca[xi+1] == yystate {
break
}
xi += 2
}
for xi += 2; ; xi += 2 {
yyn = yyExca[xi+0]
if yyn < 0 || yyn == yychar {
break
}
}
yyn = yyExca[xi+1]
if yyn < 0 {
goto ret0
}
}
if yyn == 0 {
/* error ... attempt to resume parsing */
switch Errflag {
case 0: /* brand new error */
yylex.Error("syntax error")
Nerrs++
if yyDebug >= 1 {
fmt.Printf("%s", yyStatname(yystate))
fmt.Printf("saw %s\n", yyTokname(yychar))
}
fallthrough
case 1, 2: /* incompletely recovered error ... try again */
Errflag = 3
/* find a state where "error" is a legal shift action */
for yyp >= 0 {
yyn = yyPact[yyS[yyp].yys] + yyErrCode
if yyn >= 0 && yyn < yyLast {
yystate = yyAct[yyn] /* simulate a shift of "error" */
if yyChk[yystate] == yyErrCode {
goto yystack
}
}
/* the current p has no shift on "error", pop stack */
if yyDebug >= 2 {
fmt.Printf("error recovery pops state %d\n", yyS[yyp].yys)
}
yyp--
}
/* there is no state on the stack with an error shift ... abort */
goto ret1
case 3: /* no shift yet; clobber input char */
if yyDebug >= 2 {
fmt.Printf("error recovery discards %s\n", yyTokname(yychar))
}
if yychar == yyEofCode {
goto ret1
}
yychar = -1
goto yynewstate /* try again in the same state */
}
}
/* reduction by production yyn */
if yyDebug >= 2 {
fmt.Printf("reduce %v in:\n\t%v\n", yyn, yyStatname(yystate))
}
yynt := yyn
yypt := yyp
_ = yypt // guard against "declared and not used"
yyp -= yyR2[yyn]
yyVAL = yyS[yyp+1]
/* consult goto table to find next state */
yyn = yyR1[yyn]
yyg := yyPgo[yyn]
yyj := yyg + yyS[yyp].yys + 1
if yyj >= yyLast {
yystate = yyAct[yyg]
} else {
yystate = yyAct[yyj]
if yyChk[yystate] != -yyn {
yystate = yyAct[yyg]
}
}
// dummy call; replaced with literal code
switch yynt {
case 1:
//line tuql.y:36
{
logDebugGrammar("INPUT")
}
case 3:
//line tuql.y:40
{
logDebugGrammar("PRAGMA: %v", yyS[yypt-3])
right := parsingStack.Pop()
left := parsingStack.Pop()
parser.ProcessPragma(left.(parser.Expression), right.(parser.Expression))
}
case 4:
//line tuql.y:47
{
logDebugGrammar("SELECT_STMT")
parsingQuery.ParsedSuccessfully = true
}
case 6:
//line tuql.y:52
{
parsingQuery.IsExplainOnly = true
}
case 12:
//line tuql.y:64
{
thisExpression := parsingStack.Pop()
parsingQuery.Limit = thisExpression.(parser.Expression)
}
case 13:
//line tuql.y:69
{
thisExpression := parsingStack.Pop()
parsingQuery.Offset = thisExpression.(parser.Expression)
}
case 16:
//line tuql.y:78
{
thisExpression := parser.NewSortItem(parsingStack.Pop().(parser.Expression), true)
parsingQuery.Orderby = append(parsingQuery.Orderby, *thisExpression)
}
case 17:
//line tuql.y:81
{
thisExpression := parser.NewSortItem(parsingStack.Pop().(parser.Expression), true)
parsingQuery.Orderby = append(parsingQuery.Orderby, *thisExpression)
}
case 18:
//line tuql.y:84
{
thisExpression := parser.NewSortItem(parsingStack.Pop().(parser.Expression), false)
parsingQuery.Orderby = append(parsingQuery.Orderby, *thisExpression)
}
case 19:
//line tuql.y:89
{
logDebugGrammar("SELECT_COMPOUND")
}
case 25:
//line tuql.y:99
{
logDebugGrammar("SELECT_CORE")
}
case 26:
//line tuql.y:102
{
logDebugGrammar("SELECT GROUP")
parsingQuery.IsAggregateQuery = true
parsingQuery.Groupby = parsingStack.Pop().(parser.ExpressionList)
}
case 27:
//line tuql.y:107
{
logDebugGrammar("SELECT GROUP HAVING - EMPTY")
}
case 28:
//line tuql.y:108
{
logDebugGrammar("SELECT GROUP HAVING - SELECT GROUP")
}
case 29:
//line tuql.y:109
{
logDebugGrammar("SELECT GROUP HAVING - SELECT GROUP SELECT HAVING")
}
case 30:
//line tuql.y:114
{
parsingQuery.Having = parsingStack.Pop().(parser.Expression)
}
case 31:
//line tuql.y:117
{
logDebugGrammar("SELECT WHERE - EMPTY")
}
case 32:
//line tuql.y:118
{
logDebugGrammar("SELECT WHERE - EXPR")
where_part := parsingStack.Pop()
parsingQuery.Where = where_part.(parser.Expression)
}
case 34:
//line tuql.y:124
{
logDebugGrammar("SELECT_FROM")
}
case 37:
//line tuql.y:131
{
ds := parser.NewDataSource(yyS[yypt-0].s)
parsingQuery.AddDataSource(ds)
}
case 38:
//line tuql.y:134
{
ds := parser.NewDataSource(yyS[yypt-1].s)
nextOver := parsingStack.Pop()
for nextOver != nil {
ds.AddOver(nextOver.(*parser.Over))
nextOver = parsingStack.Pop()
}
parsingQuery.AddDataSource(ds)
}
case 39:
//line tuql.y:142
{
ds := parser.NewDataSourceWithAs(yyS[yypt-2].s, yyS[yypt-0].s)
parsingQuery.AddDataSource(ds)
}
case 40:
//line tuql.y:145
{
ds := parser.NewDataSourceWithAs(yyS[yypt-3].s, yyS[yypt-1].s)
nextOver := parsingStack.Pop()
for nextOver != nil {
ds.AddOver(nextOver.(*parser.Over))
nextOver = parsingStack.Pop()
}
parsingQuery.AddDataSource(ds)
}
case 43:
//line tuql.y:159
{
prop := parsingStack.Pop().(*parser.Property)
over := parser.NewOver(prop, yyS[yypt-0].s)
parsingStack.Push(over)
}
case 45:
//line tuql.y:167
{
logDebugGrammar("SELECT_SELECT")
}
case 46:
//line tuql.y:170
{
logDebugGrammar("SELECT_SELECT_HEAD")
}
case 49:
//line tuql.y:175
{
logDebugGrammar("SELECT SELECT TAIL - EMPTY")
}
case 50:
//line tuql.y:176
{
logDebugGrammar("SELECT SELECT TAIL - EXPR")
thisExpression := parsingStack.Pop()
parsingQuery.Sel = thisExpression.(parser.Expression)
}
case 51:
//line tuql.y:182
{
logDebugGrammar("EXPRESSION")
}
case 52:
//line tuql.y:183
{
logDebugGrammar("EXPRESSION - TERNARY")
elsee := parsingStack.Pop().(parser.Expression)
thenn := parsingStack.Pop().(parser.Expression)
iff := parsingStack.Pop().(parser.Expression)
thisExpr := parser.NewTernaryExpression(iff, thenn, elsee)
parsingStack.Push(thisExpr)
}
case 53:
//line tuql.y:192
{
logDebugGrammar("EXPR - PLUS")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewPlusExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 54:
//line tuql.y:198
{
logDebugGrammar("EXPR - MINUS")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewMinusExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 55:
//line tuql.y:204
{
logDebugGrammar("EXPR - MULT")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewMultiplyExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 56:
//line tuql.y:210
{
logDebugGrammar("EXPR - DIV")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewDivideExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 57:
//line tuql.y:216
{
logDebugGrammar("EXPR - AND")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewAndExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 58:
//line tuql.y:222
{
logDebugGrammar("EXPR - OR")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewOrExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 59:
//line tuql.y:228
{
logDebugGrammar("EXPR - EQ")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewEqualsExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 60:
//line tuql.y:234
{
logDebugGrammar("EXPR - LT")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewLessThanExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 61:
//line tuql.y:240
{
logDebugGrammar("EXPR - LTE")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewLessThanOrEqualExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 62:
//line tuql.y:246
{
logDebugGrammar("EXPR - GT")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewGreaterThanExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 63:
//line tuql.y:252
{
logDebugGrammar("EXPR - GTE")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewGreaterThanOrEqualExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 64:
//line tuql.y:258
{
logDebugGrammar("EXPR - NE")
right := parsingStack.Pop()
left := parsingStack.Pop()
thisExpression := parser.NewNotEqualsExpression(left.(parser.Expression), right.(parser.Expression))
parsingStack.Push(thisExpression)
}
case 67:
//line tuql.y:269
{
logDebugGrammar("EXPR - NOT")
curr := parsingStack.Pop().(parser.Expression)
thisExpression := parser.NewNotExpression(curr)
parsingStack.Push(thisExpression)
}
case 69:
//line tuql.y:277
{
logDebugGrammar("SUFFIX_EXPR")
}
case 70:
//line tuql.y:280
{
logDebugGrammar("NULL")
thisExpression := parser.NewNull()
parsingStack.Push(thisExpression)
}
case 71:
//line tuql.y:284
{
}
case 72:
//line tuql.y:285
{
logDebugGrammar("ATOM - prop[]")
rightExpr := parsingStack.Pop().(parser.Expression)
leftProp := parsingStack.Pop().(*parser.Property)
thisExpression := parser.NewBracketMemberExpression(leftProp, rightExpr)
parsingStack.Push(thisExpression)
}
case 73:
//line tuql.y:291
{
thisExpression := parser.NewIntegerLiteral(yyS[yypt-0].n)
parsingStack.Push(thisExpression)
}
case 74:
//line tuql.y:293
{
thisExpression := parser.NewIntegerLiteral(-yyS[yypt-1].n)
parsingStack.Push(thisExpression)
}
case 75:
//line tuql.y:295
{
thisExpression := parser.NewFloatLiteral(yyS[yypt-0].f)
parsingStack.Push(thisExpression)
}
case 76:
//line tuql.y:297
{
thisExpression := parser.NewFloatLiteral(-yyS[yypt-1].f)
parsingStack.Push(thisExpression)
}
case 77:
//line tuql.y:299
{
thisExpression := parser.NewStringLiteral(yyS[yypt-0].s)
parsingStack.Push(thisExpression)
}
case 78:
//line tuql.y:301
{
thisExpression := parser.NewBoolLiteral(true)
parsingStack.Push(thisExpression)
}
case 79:
//line tuql.y:303
{
thisExpression := parser.NewBoolLiteral(false)
parsingStack.Push(thisExpression)
}
case 80:
//line tuql.y:305
{
logDebugGrammar("ATOM - {}")
}
case 81:
//line tuql.y:307
{
logDebugGrammar("ATOM - []")
exp_list := parsingStack.Pop().(parser.ExpressionList)
thisExpression := parser.NewArrayLiteral(exp_list)
parsingStack.Push(thisExpression)
}
case 82:
//line tuql.y:312
{
logDebugGrammar("FUNCTION - $1.s")
exp_list := parsingStack.Pop().(parser.ExpressionList)
function := parsingStack.Pop().(*parser.Function)
function.AddArguments(exp_list)
parsingStack.Push(function)
}
case 85:
//line tuql.y:322
{
logDebugGrammar("EXPRESSION_LIST - EXPRESSION")
exp_list := make(parser.ExpressionList, 0)
exp_list = append(exp_list, parsingStack.Pop().(parser.Expression))
parsingStack.Push(exp_list)
}
case 86:
//line tuql.y:327
{
logDebugGrammar("EXPRESSION_LIST - EXPRESSION COMMA EXPRESSION_LIST")
rest := parsingStack.Pop().(parser.ExpressionList)
last := parsingStack.Pop()
new_list := make(parser.ExpressionList, 0)
new_list = append(new_list, last.(parser.Expression))
for _, v := range rest {
new_list = append(new_list, v)
}
parsingStack.Push(new_list)
}
case 88:
//line tuql.y:340
{
last := parsingStack.Pop().(*parser.ObjectLiteral)
rest := parsingStack.Pop().(*parser.ObjectLiteral)
rest.AddAll(last)
parsingStack.Push(rest)
}
case 89:
//line tuql.y:347
{
thisKey := yyS[yypt-2].s
thisValue := parsingStack.Pop().(parser.Expression)
thisExpression := parser.NewObjectLiteral(parser.Object{thisKey: thisValue})
parsingStack.Push(thisExpression)
}
case 90:
//line tuql.y:354
{
thisExpression := parser.NewProperty(yyS[yypt-0].s)
parsingStack.Push(thisExpression)
}
case 91:
//line tuql.y:358
{
thisValue := parsingStack.Pop().(*parser.Property)
thisExpression := parser.NewProperty(yyS[yypt-2].s + "." + thisValue.Symbol)
parsingStack.Push(thisExpression)
}
case 92:
//line tuql.y:365
{
parsingQuery.IsAggregateQuery = true
thisExpression := parser.NewFunction("min")
parsingStack.Push(thisExpression)
}
case 93:
//line tuql.y:370
{
parsingQuery.IsAggregateQuery = true
thisExpression := parser.NewFunction("max")
parsingStack.Push(thisExpression)
}
case 94:
//line tuql.y:375
{
parsingQuery.IsAggregateQuery = true
thisExpression := parser.NewFunction("avg")
parsingStack.Push(thisExpression)
}
case 95:
//line tuql.y:380
{
parsingQuery.IsAggregateQuery = true
thisExpression := parser.NewFunction("count")
parsingStack.Push(thisExpression)
}
case 96:
//line tuql.y:385
{
parsingQuery.IsAggregateQuery = true
thisExpression := parser.NewFunction("sum")
parsingStack.Push(thisExpression)
}
}
goto yystack /* stack new state and value */
}