master
兔子 1 year ago
commit babb5963b5

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// Modeling of columns
package sqlbuilder
import (
"bytes"
"regexp"
"github.com/dropbox/godropbox/errors"
)
// XXX: Maybe add UIntColumn
// Representation of a table for query generation
type Column interface {
isProjectionInterface
Name() string
// Serialization for use in column lists
SerializeSqlForColumnList(out *bytes.Buffer) error
// Serialization for use in an expression (Clause)
SerializeSql(out *bytes.Buffer) error
// Internal function for tracking table that a column belongs to
// for the purpose of serialization
setTableName(table string) error
}
type NullableColumn bool
const (
Nullable NullableColumn = true
NotNullable NullableColumn = false
)
// A column that can be refer to outside of the projection list
type NonAliasColumn interface {
Column
isOrderByClauseInterface
isExpressionInterface
}
type Collation string
const (
UTF8CaseInsensitive Collation = "utf8_unicode_ci"
UTF8CaseSensitive Collation = "utf8_unicode"
UTF8Binary Collation = "utf8_bin"
)
// Representation of MySQL charsets
type Charset string
const (
UTF8 Charset = "utf8"
)
// The base type for real materialized columns.
type baseColumn struct {
isProjection
isExpression
name string
nullable NullableColumn
table string
}
func (c *baseColumn) Name() string {
return c.name
}
func (c *baseColumn) setTableName(table string) error {
c.table = table
return nil
}
/*func (c *baseColumn) SerializeSqlForColumnList(out *bytes.Buffer) error {
if c.table != "" {
_ = out.WriteByte('`')
_, _ = out.WriteString(c.table)
_, _ = out.WriteString("`.")
}
_, _ = out.WriteString("`")
_, _ = out.WriteString(c.name)
_ = out.WriteByte('`')
return nil
}
*/
func (c *baseColumn) SerializeSqlForColumnList(out *bytes.Buffer) error {
// Momo modified. we don't need prefixing table name
/*
if c.table != "" {
_ = out.WriteByte('`')
_, _ = out.WriteString(c.table)
_, _ = out.WriteString("`.")
}
*/
_, _ = out.WriteString("`")
_, _ = out.WriteString(c.name)
_ = out.WriteByte('`')
return nil
}
func (c *baseColumn) SerializeSql(out *bytes.Buffer) error {
return c.SerializeSqlForColumnList(out)
}
type bytesColumn struct {
baseColumn
isExpression
}
// Representation of VARBINARY/BLOB columns
// This function will panic if name is not valid
func BytesColumn(name string, nullable NullableColumn) NonAliasColumn {
if !validIdentifierName(name) {
panic("Invalid column name in bytes column")
}
bc := &bytesColumn{}
bc.name = name
bc.nullable = nullable
return bc
}
type stringColumn struct {
baseColumn
isExpression
charset Charset
collation Collation
}
// Representation of VARCHAR/TEXT columns
// This function will panic if name is not valid
func StrColumn(
name string,
charset Charset,
collation Collation,
nullable NullableColumn) NonAliasColumn {
if !validIdentifierName(name) {
panic("Invalid column name in str column")
}
sc := &stringColumn{charset: charset, collation: collation}
sc.name = name
sc.nullable = nullable
return sc
}
type dateTimeColumn struct {
baseColumn
isExpression
}
// Representation of DateTime columns
// This function will panic if name is not valid
func DateTimeColumn(name string, nullable NullableColumn) NonAliasColumn {
if !validIdentifierName(name) {
panic("Invalid column name in datetime column")
}
dc := &dateTimeColumn{}
dc.name = name
dc.nullable = nullable
return dc
}
type integerColumn struct {
baseColumn
isExpression
}
// Representation of any integer column
// This function will panic if name is not valid
func IntColumn(name string, nullable NullableColumn) NonAliasColumn {
if !validIdentifierName(name) {
panic("Invalid column name in int column")
}
ic := &integerColumn{}
ic.name = name
ic.nullable = nullable
return ic
}
type doubleColumn struct {
baseColumn
isExpression
}
// Representation of any double column
// This function will panic if name is not valid
func DoubleColumn(name string, nullable NullableColumn) NonAliasColumn {
if !validIdentifierName(name) {
panic("Invalid column name in int column")
}
ic := &doubleColumn{}
ic.name = name
ic.nullable = nullable
return ic
}
type booleanColumn struct {
baseColumn
isExpression
// XXX: Maybe allow isBoolExpression (for now, not included because
// the deferred lookup equivalent can never be isBoolExpression)
}
// Representation of TINYINT used as a bool
// This function will panic if name is not valid
func BoolColumn(name string, nullable NullableColumn) NonAliasColumn {
if !validIdentifierName(name) {
panic("Invalid column name in bool column")
}
bc := &booleanColumn{}
bc.name = name
bc.nullable = nullable
return bc
}
type aliasColumn struct {
baseColumn
expression Expression
}
func (c *aliasColumn) SerializeSql(out *bytes.Buffer) error {
_ = out.WriteByte('`')
_, _ = out.WriteString(c.name)
_ = out.WriteByte('`')
return nil
}
func (c *aliasColumn) SerializeSqlForColumnList(out *bytes.Buffer) error {
if !validIdentifierName(c.name) {
return errors.Newf(
"Invalid alias name `%s`. Generated sql: %s",
c.name,
out.String())
}
if c.expression == nil {
return errors.Newf(
"Cannot alias a nil expression. Generated sql: %s",
out.String())
}
_ = out.WriteByte('(')
if c.expression == nil {
return errors.Newf("nil alias clause. Generate sql: %s", out.String())
}
if err := c.expression.SerializeSql(out); err != nil {
return err
}
_, _ = out.WriteString(") AS `")
_, _ = out.WriteString(c.name)
_ = out.WriteByte('`')
return nil
}
func (c *aliasColumn) setTableName(table string) error {
return errors.Newf(
"Alias column '%s' should never have setTableName called on it",
c.name)
}
// Representation of aliased clauses (expression AS name)
func Alias(name string, c Expression) Column {
ac := &aliasColumn{}
ac.name = name
ac.expression = c
return ac
}
// This is a strict subset of the actual allowed identifiers
var validIdentifierRegexp = regexp.MustCompile("^[a-zA-Z_]\\w*$")
// Returns true if the given string is suitable as an identifier.
func validIdentifierName(name string) bool {
//return validIdentifierRegexp.MatchString(name)
return true
}
// Pseudo Column type returned by table.C(name)
type deferredLookupColumn struct {
isProjection
isExpression
table *Table
colName string
cachedColumn NonAliasColumn
}
func (c *deferredLookupColumn) Name() string {
return c.colName
}
func (c *deferredLookupColumn) SerializeSqlForColumnList(
out *bytes.Buffer) error {
return c.SerializeSql(out)
}
func (c *deferredLookupColumn) SerializeSql(out *bytes.Buffer) error {
if c.cachedColumn != nil {
return c.cachedColumn.SerializeSql(out)
}
col, err := c.table.getColumn(c.colName)
if err != nil {
return err
}
c.cachedColumn = col
return col.SerializeSql(out)
}
func (c *deferredLookupColumn) setTableName(table string) error {
return errors.Newf(
"Lookup column '%s' should never have setTableName called on it",
c.colName)
}

@ -0,0 +1,25 @@
// A library for generating sql programmatically.
//
// SQL COMPATIBILITY NOTE: sqlbuilder is designed to generate valid MySQL sql
// statements. The generated statements may not work for other sql variants.
// For instances, the generated statements does not currently work for
// PostgreSQL since column identifiers are escaped with backquotes.
// Patches to support other sql flavors are welcome! (see
// https://godropbox/issues/33 for additional details).
//
// Known limitations for SELECT queries:
// - does not support subqueries (since mysql is bad at it)
// - does not currently support join table alias (and hence self join)
// - does not support NATURAL joins and join USING
//
// Known limitation for INSERT statements:
// - does not support "INSERT INTO SELECT"
//
// Known limitation for UPDATE statements:
// - does not support update without a WHERE clause (since it is dangerous)
// - does not support multi-table update
//
// Known limitation for DELETE statements:
// - does not support delete without a WHERE clause (since it is dangerous)
// - does not support multi-table delete
package sqlbuilder

@ -0,0 +1,733 @@
// Query building functions for expression components
package sqlbuilder
import (
"bytes"
"reflect"
"strconv"
"strings"
"time"
"b612.me/mysql/sqltypes"
"github.com/dropbox/godropbox/errors"
)
type orderByClause struct {
isOrderByClause
expression Expression
ascent bool
}
func (o *orderByClause) SerializeSql(out *bytes.Buffer) error {
if o.expression == nil {
return errors.Newf(
"nil order by clause. Generated sql: %s",
out.String())
}
if err := o.expression.SerializeSql(out); err != nil {
return err
}
if o.ascent {
_, _ = out.WriteString(" ASC")
} else {
_, _ = out.WriteString(" DESC")
}
return nil
}
func Asc(expression Expression) OrderByClause {
return &orderByClause{expression: expression, ascent: true}
}
func Desc(expression Expression) OrderByClause {
return &orderByClause{expression: expression, ascent: false}
}
// Representation of an escaped literal
type literalExpression struct {
isExpression
value sqltypes.Value
}
func (c literalExpression) SerializeSql(out *bytes.Buffer) error {
sqltypes.Value(c.value).EncodeSql(out)
return nil
}
func serializeClauses(
clauses []Clause,
separator []byte,
out *bytes.Buffer) (err error) {
if clauses == nil || len(clauses) == 0 {
return errors.Newf("Empty clauses. Generated sql: %s", out.String())
}
if clauses[0] == nil {
return errors.Newf("nil clause. Generated sql: %s", out.String())
}
if err = clauses[0].SerializeSql(out); err != nil {
return
}
for _, c := range clauses[1:] {
_, _ = out.Write(separator)
if c == nil {
return errors.Newf("nil clause. Generated sql: %s", out.String())
}
if err = c.SerializeSql(out); err != nil {
return
}
}
return nil
}
// Representation of n-ary conjunctions (AND/OR)
type conjunctExpression struct {
isExpression
isBoolExpression
expressions []BoolExpression
conjunction []byte
}
func (conj *conjunctExpression) SerializeSql(out *bytes.Buffer) (err error) {
if len(conj.expressions) == 0 {
return errors.Newf(
"Empty conjunction. Generated sql: %s",
out.String())
}
clauses := make([]Clause, len(conj.expressions), len(conj.expressions))
for i, expr := range conj.expressions {
clauses[i] = expr
}
useParentheses := len(clauses) > 1
if useParentheses {
_ = out.WriteByte('(')
}
if err = serializeClauses(clauses, conj.conjunction, out); err != nil {
return
}
if useParentheses {
_ = out.WriteByte(')')
}
return nil
}
// Representation of n-ary arithmetic (+ - * /)
type arithmeticExpression struct {
isExpression
expressions []Expression
operator []byte
}
func (arith *arithmeticExpression) SerializeSql(out *bytes.Buffer) (err error) {
if len(arith.expressions) == 0 {
return errors.Newf(
"Empty arithmetic expression. Generated sql: %s",
out.String())
}
clauses := make([]Clause, len(arith.expressions), len(arith.expressions))
for i, expr := range arith.expressions {
clauses[i] = expr
}
useParentheses := len(clauses) > 1
if useParentheses {
_ = out.WriteByte('(')
}
if err = serializeClauses(clauses, arith.operator, out); err != nil {
return
}
if useParentheses {
_ = out.WriteByte(')')
}
return nil
}
type tupleExpression struct {
isExpression
elements listClause
}
func (tuple *tupleExpression) SerializeSql(out *bytes.Buffer) error {
if len(tuple.elements.clauses) < 1 {
return errors.Newf("Tuples must include at least one element")
}
return tuple.elements.SerializeSql(out)
}
func Tuple(exprs ...Expression) Expression {
clauses := make([]Clause, 0, len(exprs))
for _, expr := range exprs {
clauses = append(clauses, expr)
}
return &tupleExpression{
elements: listClause{
clauses: clauses,
includeParentheses: true,
},
}
}
// Representation of a tuple enclosed, comma separated list of clauses
type listClause struct {
clauses []Clause
includeParentheses bool
}
func (list *listClause) SerializeSql(out *bytes.Buffer) error {
if list.includeParentheses {
_ = out.WriteByte('(')
}
if err := serializeClauses(list.clauses, []byte(","), out); err != nil {
return err
}
if list.includeParentheses {
_ = out.WriteByte(')')
}
return nil
}
// A not expression which negates a expression value
type negateExpression struct {
isExpression
isBoolExpression
nested BoolExpression
}
func (c *negateExpression) SerializeSql(out *bytes.Buffer) (err error) {
_, _ = out.WriteString("NOT (")
if c.nested == nil {
return errors.Newf("nil nested. Generated sql: %s", out.String())
}
if err = c.nested.SerializeSql(out); err != nil {
return
}
_ = out.WriteByte(')')
return nil
}
// Returns a representation of "not expr"
func Not(expr BoolExpression) BoolExpression {
return &negateExpression{
nested: expr,
}
}
// Representation of binary operations (e.g. comparisons, arithmetic)
type binaryExpression struct {
isExpression
lhs, rhs Expression
operator []byte
}
func (c *binaryExpression) SerializeSql(out *bytes.Buffer) (err error) {
if c.lhs == nil {
return errors.Newf("nil lhs. Generated sql: %s", out.String())
}
if err = c.lhs.SerializeSql(out); err != nil {
return
}
_, _ = out.Write(c.operator)
if c.rhs == nil {
return errors.Newf("nil rhs. Generated sql: %s", out.String())
}
if err = c.rhs.SerializeSql(out); err != nil {
return
}
return nil
}
// A binary expression that evaluates to a boolean value.
type boolExpression struct {
isBoolExpression
binaryExpression
}
func newBoolExpression(lhs, rhs Expression, operator []byte) *boolExpression {
// go does not allow {} syntax for initializing promoted fields ...
expr := new(boolExpression)
expr.lhs = lhs
expr.rhs = rhs
expr.operator = operator
return expr
}
type funcExpression struct {
isExpression
funcName string
args *listClause
}
func (c *funcExpression) SerializeSql(out *bytes.Buffer) (err error) {
if !validIdentifierName(c.funcName) {
return errors.Newf(
"Invalid function name: %s. Generated sql: %s",
c.funcName,
out.String())
}
_, _ = out.WriteString(c.funcName)
if c.args == nil {
_, _ = out.WriteString("()")
} else {
return c.args.SerializeSql(out)
}
return nil
}
// Returns a representation of sql function call "func_call(c[0], ..., c[n-1])
func SqlFunc(funcName string, expressions ...Expression) Expression {
f := &funcExpression{
funcName: funcName,
}
if len(expressions) > 0 {
args := make([]Clause, len(expressions), len(expressions))
for i, expr := range expressions {
args[i] = expr
}
f.args = &listClause{
clauses: args,
includeParentheses: true,
}
}
return f
}
type intervalExpression struct {
isExpression
duration time.Duration
negative bool
}
var intervalSep = ":"
func (c *intervalExpression) SerializeSql(out *bytes.Buffer) (err error) {
hours := c.duration / time.Hour
minutes := (c.duration % time.Hour) / time.Minute
sec := (c.duration % time.Minute) / time.Second
msec := (c.duration % time.Second) / time.Microsecond
_, _ = out.WriteString("INTERVAL '")
if c.negative {
_, _ = out.WriteString("-")
}
_, _ = out.WriteString(strconv.FormatInt(int64(hours), 10))
_, _ = out.WriteString(intervalSep)
_, _ = out.WriteString(strconv.FormatInt(int64(minutes), 10))
_, _ = out.WriteString(intervalSep)
_, _ = out.WriteString(strconv.FormatInt(int64(sec), 10))
_, _ = out.WriteString(intervalSep)
_, _ = out.WriteString(strconv.FormatInt(int64(msec), 10))
_, _ = out.WriteString("' HOUR_MICROSECOND")
return nil
}
// Interval returns a representation of duration
// in a form "INTERVAL `hour:min:sec:microsec` HOUR_MICROSECOND"
func Interval(duration time.Duration) Expression {
negative := false
if duration < 0 {
negative = true
duration = -duration
}
return &intervalExpression{
duration: duration,
negative: negative,
}
}
var likeEscaper = strings.NewReplacer("_", "\\_", "%", "\\%")
func EscapeForLike(s string) string {
return likeEscaper.Replace(s)
}
// Returns an escaped literal string
func Literal(v interface{}) Expression {
value, err := sqltypes.BuildValue(v)
if err != nil {
panic(errors.Wrap(err, "Invalid literal value"))
}
return &literalExpression{value: value}
}
// Returns a representation of "c[0] AND ... AND c[n-1]" for c in clauses
func And(expressions ...BoolExpression) BoolExpression {
return &conjunctExpression{
expressions: expressions,
conjunction: []byte(" AND "),
}
}
// Returns a representation of "c[0] OR ... OR c[n-1]" for c in clauses
func Or(expressions ...BoolExpression) BoolExpression {
return &conjunctExpression{
expressions: expressions,
conjunction: []byte(" OR "),
}
}
func Like(lhs, rhs Expression) BoolExpression {
return newBoolExpression(lhs, rhs, []byte(" LIKE "))
}
func LikeL(lhs Expression, val string) BoolExpression {
return Like(lhs, Literal(val))
}
func Regexp(lhs, rhs Expression) BoolExpression {
return newBoolExpression(lhs, rhs, []byte(" REGEXP "))
}
func RegexpL(lhs Expression, val string) BoolExpression {
return Regexp(lhs, Literal(val))
}
// Returns a representation of "c[0] + ... + c[n-1]" for c in clauses
func Add(expressions ...Expression) Expression {
return &arithmeticExpression{
expressions: expressions,
operator: []byte(" + "),
}
}
// Returns a representation of "c[0] - ... - c[n-1]" for c in clauses
func Sub(expressions ...Expression) Expression {
return &arithmeticExpression{
expressions: expressions,
operator: []byte(" - "),
}
}
// Returns a representation of "c[0] * ... * c[n-1]" for c in clauses
func Mul(expressions ...Expression) Expression {
return &arithmeticExpression{
expressions: expressions,
operator: []byte(" * "),
}
}
// Returns a representation of "c[0] / ... / c[n-1]" for c in clauses
func Div(expressions ...Expression) Expression {
return &arithmeticExpression{
expressions: expressions,
operator: []byte(" / "),
}
}
// Returns a representation of "a=b"
func Eq(lhs, rhs Expression) BoolExpression {
lit, ok := rhs.(*literalExpression)
if ok && sqltypes.Value(lit.value).IsNull() {
return newBoolExpression(lhs, rhs, []byte(" IS "))
}
return newBoolExpression(lhs, rhs, []byte("="))
}
// Returns a representation of "a=b", where b is a literal
func EqL(lhs Expression, val interface{}) BoolExpression {
return Eq(lhs, Literal(val))
}
// Returns a representation of "a!=b"
func Neq(lhs, rhs Expression) BoolExpression {
lit, ok := rhs.(*literalExpression)
if ok && sqltypes.Value(lit.value).IsNull() {
return newBoolExpression(lhs, rhs, []byte(" IS NOT "))
}
return newBoolExpression(lhs, rhs, []byte("!="))
}
// Returns a representation of "a!=b", where b is a literal
func NeqL(lhs Expression, val interface{}) BoolExpression {
return Neq(lhs, Literal(val))
}
// Returns a representation of "a<b"
func Lt(lhs Expression, rhs Expression) BoolExpression {
return newBoolExpression(lhs, rhs, []byte("<"))
}
// Returns a representation of "a<b", where b is a literal
func LtL(lhs Expression, val interface{}) BoolExpression {
return Lt(lhs, Literal(val))
}
// Returns a representation of "a<=b"
func Lte(lhs, rhs Expression) BoolExpression {
return newBoolExpression(lhs, rhs, []byte("<="))
}
// Returns a representation of "a<=b", where b is a literal
func LteL(lhs Expression, val interface{}) BoolExpression {
return Lte(lhs, Literal(val))
}
// Returns a representation of "a>b"
func Gt(lhs, rhs Expression) BoolExpression {
return newBoolExpression(lhs, rhs, []byte(">"))
}
// Returns a representation of "a>b", where b is a literal
func GtL(lhs Expression, val interface{}) BoolExpression {
return Gt(lhs, Literal(val))
}
// Returns a representation of "a>=b"
func Gte(lhs, rhs Expression) BoolExpression {
return newBoolExpression(lhs, rhs, []byte(">="))
}
// Returns a representation of "a>=b", where b is a literal
func GteL(lhs Expression, val interface{}) BoolExpression {
return Gte(lhs, Literal(val))
}
func BitOr(lhs, rhs Expression) Expression {
return &binaryExpression{
lhs: lhs,
rhs: rhs,
operator: []byte(" | "),
}
}
func BitAnd(lhs, rhs Expression) Expression {
return &binaryExpression{
lhs: lhs,
rhs: rhs,
operator: []byte(" & "),
}
}
func BitXor(lhs, rhs Expression) Expression {
return &binaryExpression{
lhs: lhs,
rhs: rhs,
operator: []byte(" ^ "),
}
}
func Plus(lhs, rhs Expression) Expression {
return &binaryExpression{
lhs: lhs,
rhs: rhs,
operator: []byte(" + "),
}
}
func Minus(lhs, rhs Expression) Expression {
return &binaryExpression{
lhs: lhs,
rhs: rhs,
operator: []byte(" - "),
}
}
// in expression representation
type inExpression struct {
isExpression
isBoolExpression
lhs Expression
rhs *listClause
err error
}
func (c *inExpression) SerializeSql(out *bytes.Buffer) error {
if c.err != nil {
return errors.Wrap(c.err, "Invalid IN expression")
}
if c.lhs == nil {
return errors.Newf(
"lhs of in expression is nil. Generated sql: %s",
out.String())
}
// We'll serialize the lhs even if we don't need it to ensure no error
buf := &bytes.Buffer{}
err := c.lhs.SerializeSql(buf)
if err != nil {
return err
}
if c.rhs == nil {
_, _ = out.WriteString("FALSE")
return nil
}
_, _ = out.WriteString(buf.String())
_, _ = out.WriteString(" IN ")
err = c.rhs.SerializeSql(out)
if err != nil {
return err
}
return nil
}
// Returns a representation of "a IN (b[0], ..., b[n-1])", where b is a list
// of literals valList must be a slice type
func In(lhs Expression, valList interface{}) BoolExpression {
var clauses []Clause
switch val := valList.(type) {
// This atrocious body of copy-paste code is due to the fact that if you
// try to merge the cases, you can't treat val as a list
case []int:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []int32:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []int64:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []uint:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []uint32:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []uint64:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []float64:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []string:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case [][]byte:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []time.Time:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []sqltypes.Numeric:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []sqltypes.Fractional:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []sqltypes.String:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
case []sqltypes.Value:
clauses = make([]Clause, 0, len(val))
for _, v := range val {
clauses = append(clauses, Literal(v))
}
default:
return &inExpression{
err: errors.Newf(
"Unknown value list type in IN clause: %s",
reflect.TypeOf(valList)),
}
}
expr := &inExpression{lhs: lhs}
if len(clauses) > 0 {
expr.rhs = &listClause{clauses: clauses, includeParentheses: true}
}
return expr
}
type ifExpression struct {
isExpression
conditional BoolExpression
trueExpression Expression
falseExpression Expression
}
func (exp *ifExpression) SerializeSql(out *bytes.Buffer) error {
_, _ = out.WriteString("IF(")
_ = exp.conditional.SerializeSql(out)
_, _ = out.WriteString(",")
_ = exp.trueExpression.SerializeSql(out)
_, _ = out.WriteString(",")
_ = exp.falseExpression.SerializeSql(out)
_, _ = out.WriteString(")")
return nil
}
// Returns a representation of an if-expression, of the form:
//
// IF (BOOLEAN TEST, VALUE-IF-TRUE, VALUE-IF-FALSE)
func If(conditional BoolExpression,
trueExpression Expression,
falseExpression Expression) Expression {
return &ifExpression{
conditional: conditional,
trueExpression: trueExpression,
falseExpression: falseExpression,
}
}
type columnValueExpression struct {
isExpression
column NonAliasColumn
}
func ColumnValue(col NonAliasColumn) Expression {
return &columnValueExpression{
column: col,
}
}
func (cv *columnValueExpression) SerializeSql(out *bytes.Buffer) error {
_, _ = out.WriteString("VALUES(")
_ = cv.column.SerializeSqlForColumnList(out)
_ = out.WriteByte(')')
return nil
}

@ -0,0 +1,8 @@
module b612.me/mysql/sqlbuilder
go 1.20
require (
b612.me/mysql/sqltypes v0.0.0-20230701101652-40406d9a2ff2
github.com/dropbox/godropbox v0.0.0-20230623171840-436d2007a9fd
)

@ -0,0 +1,33 @@
b612.me/mysql/sqltypes v0.0.0-20230701101652-40406d9a2ff2 h1:gWGuBHC7hrmyhp9vX1UOOX5C9WRoFHPDjSvRfmP/nS4=
b612.me/mysql/sqltypes v0.0.0-20230701101652-40406d9a2ff2/go.mod h1:Py9XWC9lc2cDhzfSPO7gqk07qZcPpJfk0aQ0iUZC5CQ=
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/dropbox/godropbox v0.0.0-20230623171840-436d2007a9fd h1:s2vYw+2c+7GR1ccOaDuDcKsmNB/4RIxyu5liBm1VRbs=
github.com/dropbox/godropbox v0.0.0-20230623171840-436d2007a9fd/go.mod h1:Vr/Q4p40Kce7JAHDITjDhiy/zk07W4tqD5YVi5FD0PA=
github.com/gogo/protobuf v1.3.1/go.mod h1:SlYgWuQ5SjCEi6WLHjHCa1yvBfUnHcTbrrZtXPKa29o=
github.com/kisielk/errcheck v1.2.0/go.mod h1:/BMXB+zMLi60iA8Vv6Ksmxu/1UDYcXs4uQLJ+jE2L00=
github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
github.com/kr/pretty v0.2.0 h1:s5hAObm+yFO5uHYt5dYjxi2rXrsnmRpJx4OYvIWUaQs=
github.com/kr/pretty v0.2.0/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
github.com/stretchr/testify v1.8.0 h1:pSgiaMZlXftHpm5L7V1+rVB+AZJydKsMxsQBIJw4PKk=
github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/net v0.0.0-20200202094626-16171245cfb2/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
golang.org/x/tools v0.0.0-20181030221726-6c7e314b6563/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

File diff suppressed because it is too large Load Diff

@ -0,0 +1,321 @@
// Modeling of tables. This is where query preparation starts
package sqlbuilder
import (
"bytes"
"fmt"
"github.com/dropbox/godropbox/errors"
)
// The sql table read interface. NOTE: NATURAL JOINs, and join "USING" clause
// are not supported.
type ReadableTable interface {
// Returns the list of columns that are in the current table expression.
Columns() []NonAliasColumn
// Generates the sql string for the current table expression. Note: the
// generated string may not be a valid/executable sql statement.
// The database is the name of the database the table is on
SerializeSql(database string, out *bytes.Buffer) error
// Generates a select query on the current table.
Select(projections ...Projection) SelectStatement
// Creates a inner join table expression using onCondition.
InnerJoinOn(table ReadableTable, onCondition BoolExpression) ReadableTable
// Creates a left join table expression using onCondition.
LeftJoinOn(table ReadableTable, onCondition BoolExpression) ReadableTable
// Creates a right join table expression using onCondition.
RightJoinOn(table ReadableTable, onCondition BoolExpression) ReadableTable
}
// The sql table write interface.
type WritableTable interface {
// Returns the list of columns that are in the table.
Columns() []NonAliasColumn
// Generates the sql string for the current table expression. Note: the
// generated string may not be a valid/executable sql statement.
// The database is the name of the database the table is on
SerializeSql(database string, out *bytes.Buffer) error
Insert(columns ...NonAliasColumn) InsertStatement
Update() UpdateStatement
Delete() DeleteStatement
}
// Defines a physical table in the database that is both readable and writable.
// This function will panic if name is not valid
func NewTable(name string, columns ...NonAliasColumn) *Table {
if !validIdentifierName(name) {
panic("Invalid table name")
}
t := &Table{
name: name,
columns: columns,
columnLookup: make(map[string]NonAliasColumn),
}
for _, c := range columns {
err := c.setTableName(name)
if err != nil {
panic(err)
}
t.columnLookup[c.Name()] = c
}
if len(columns) == 0 {
panic(fmt.Sprintf("Table %s has no columns", name))
}
return t
}
type Table struct {
name string
columns []NonAliasColumn
columnLookup map[string]NonAliasColumn
// If not empty, the name of the index to force
forcedIndex string
}
// Returns the specified column, or errors if it doesn't exist in the table
func (t *Table) getColumn(name string) (NonAliasColumn, error) {
if c, ok := t.columnLookup[name]; ok {
return c, nil
}
return nil, errors.Newf("No such column '%s' in table '%s'", name, t.name)
}
// Returns a pseudo column representation of the column name. Error checking
// is deferred to SerializeSql.
func (t *Table) C(name string) NonAliasColumn {
return &deferredLookupColumn{
table: t,
colName: name,
}
}
// Returns all columns for a table as a slice of projections
func (t *Table) Projections() []Projection {
result := make([]Projection, 0)
for _, col := range t.columns {
result = append(result, col)
}
return result
}
// Returns the table's name in the database
func (t *Table) Name() string {
return t.name
}
// Returns a list of the table's columns
func (t *Table) Columns() []NonAliasColumn {
return t.columns
}
// Returns a copy of this table, but with the specified index forced.
func (t *Table) ForceIndex(index string) *Table {
newTable := *t
newTable.forcedIndex = index
return &newTable
}
// Generates the sql string for the current table expression. Note: the
// generated string may not be a valid/executable sql statement.
func (t *Table) SerializeSql(database string, out *bytes.Buffer) error {
//Momo modified. if database empty, not write
if database != "" {
_, _ = out.WriteString("`")
_, _ = out.WriteString(database)
_, _ = out.WriteString("`.")
}
_, _ = out.WriteString("`")
_, _ = out.WriteString(t.Name())
_, _ = out.WriteString("`")
if t.forcedIndex != "" {
if !validIdentifierName(t.forcedIndex) {
return errors.Newf("'%s' is not a valid identifier for an index", t.forcedIndex)
}
_, _ = out.WriteString(" FORCE INDEX (`")
_, _ = out.WriteString(t.forcedIndex)
_, _ = out.WriteString("`)")
}
return nil
}
// Generates a select query on the current table.
func (t *Table) Select(projections ...Projection) SelectStatement {
return newSelectStatement(t, projections)
}
// Creates a inner join table expression using onCondition.
func (t *Table) InnerJoinOn(
table ReadableTable,
onCondition BoolExpression) ReadableTable {
return InnerJoinOn(t, table, onCondition)
}
// Creates a left join table expression using onCondition.
func (t *Table) LeftJoinOn(
table ReadableTable,
onCondition BoolExpression) ReadableTable {
return LeftJoinOn(t, table, onCondition)
}
// Creates a right join table expression using onCondition.
func (t *Table) RightJoinOn(
table ReadableTable,
onCondition BoolExpression) ReadableTable {
return RightJoinOn(t, table, onCondition)
}
func (t *Table) Insert(columns ...NonAliasColumn) InsertStatement {
return newInsertStatement(t, columns...)
}
func (t *Table) Update() UpdateStatement {
return newUpdateStatement(t)
}
func (t *Table) Delete() DeleteStatement {
return newDeleteStatement(t)
}
type joinType int
const (
INNER_JOIN joinType = iota
LEFT_JOIN
RIGHT_JOIN
)
// Join expressions are pseudo readable tables.
type joinTable struct {
lhs ReadableTable
rhs ReadableTable
join_type joinType
onCondition BoolExpression
}
func newJoinTable(
lhs ReadableTable,
rhs ReadableTable,
join_type joinType,
onCondition BoolExpression) ReadableTable {
return &joinTable{
lhs: lhs,
rhs: rhs,
join_type: join_type,
onCondition: onCondition,
}
}
func InnerJoinOn(
lhs ReadableTable,
rhs ReadableTable,
onCondition BoolExpression) ReadableTable {
return newJoinTable(lhs, rhs, INNER_JOIN, onCondition)
}
func LeftJoinOn(
lhs ReadableTable,
rhs ReadableTable,
onCondition BoolExpression) ReadableTable {
return newJoinTable(lhs, rhs, LEFT_JOIN, onCondition)
}
func RightJoinOn(
lhs ReadableTable,
rhs ReadableTable,
onCondition BoolExpression) ReadableTable {
return newJoinTable(lhs, rhs, RIGHT_JOIN, onCondition)
}
func (t *joinTable) Columns() []NonAliasColumn {
columns := make([]NonAliasColumn, 0)
columns = append(columns, t.lhs.Columns()...)
columns = append(columns, t.rhs.Columns()...)
return columns
}
func (t *joinTable) SerializeSql(
database string,
out *bytes.Buffer) (err error) {
if t.lhs == nil {
return errors.Newf("nil lhs. Generated sql: %s", out.String())
}
if t.rhs == nil {
return errors.Newf("nil rhs. Generated sql: %s", out.String())
}
if t.onCondition == nil {
return errors.Newf("nil onCondition. Generated sql: %s", out.String())
}
if err = t.lhs.SerializeSql(database, out); err != nil {
return
}
switch t.join_type {
case INNER_JOIN:
_, _ = out.WriteString(" JOIN ")
case LEFT_JOIN:
_, _ = out.WriteString(" LEFT JOIN ")
case RIGHT_JOIN:
_, _ = out.WriteString(" RIGHT JOIN ")
}
if err = t.rhs.SerializeSql(database, out); err != nil {
return
}
_, _ = out.WriteString(" ON ")
if err = t.onCondition.SerializeSql(out); err != nil {
return
}
return nil
}
func (t *joinTable) Select(projections ...Projection) SelectStatement {
return newSelectStatement(t, projections)
}
func (t *joinTable) InnerJoinOn(
table ReadableTable,
onCondition BoolExpression) ReadableTable {
return InnerJoinOn(t, table, onCondition)
}
func (t *joinTable) LeftJoinOn(
table ReadableTable,
onCondition BoolExpression) ReadableTable {
return LeftJoinOn(t, table, onCondition)
}
func (t *joinTable) RightJoinOn(
table ReadableTable,
onCondition BoolExpression) ReadableTable {
return RightJoinOn(t, table, onCondition)
}

@ -0,0 +1,26 @@
package sqlbuilder
var table1Col1 = IntColumn("col1", Nullable)
var table1Col2 = IntColumn("col2", Nullable)
var table1Col3 = IntColumn("col3", Nullable)
var table1Col4 = DateTimeColumn("col4", Nullable)
var table1 = NewTable(
"table1",
table1Col1,
table1Col2,
table1Col3,
table1Col4)
var table2Col3 = IntColumn("col3", Nullable)
var table2Col4 = IntColumn("col4", Nullable)
var table2 = NewTable(
"table2",
table2Col3,
table2Col4)
var table3Col1 = IntColumn("col1", Nullable)
var table3Col2 = IntColumn("col2", Nullable)
var table3 = NewTable(
"table3",
table3Col1,
table3Col2)

@ -0,0 +1,79 @@
package sqlbuilder
import (
"bytes"
)
type Clause interface {
SerializeSql(out *bytes.Buffer) error
}
// A clause that can be used in order by
type OrderByClause interface {
Clause
isOrderByClauseInterface
}
// An expression
type Expression interface {
Clause
isExpressionInterface
}
type BoolExpression interface {
Clause
isBoolExpressionInterface
}
// A clause that is selectable.
type Projection interface {
Clause
isProjectionInterface
SerializeSqlForColumnList(out *bytes.Buffer) error
}
//
// Boiler plates ...
//
type isOrderByClauseInterface interface {
isOrderByClauseType()
}
type isOrderByClause struct {
}
func (o *isOrderByClause) isOrderByClauseType() {
}
type isExpressionInterface interface {
isExpressionType()
}
type isExpression struct {
isOrderByClause // can always use expression in order by.
}
func (e *isExpression) isExpressionType() {
}
type isBoolExpressionInterface interface {
isExpressionInterface
isBoolExpressionType()
}
type isBoolExpression struct {
}
func (e *isBoolExpression) isBoolExpressionType() {
}
type isProjectionInterface interface {
isProjectionType()
}
type isProjection struct {
}
func (p *isProjection) isProjectionType() {
}
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