Builder

Builder 是一个 XORM 内置的轻量级快速 SQL 构建引擎。

请注意此包为独立安装，请确保你的 Go 版本在 1.8+ 以上可以如下安装。

go get xorm.io/builder

Insert

sql, args, err := builder.Insert(Eq{"c": 1, "d": 2}).Into("table1").ToSQL()
// INSERT INTO table1 SELECT * FROM table2
sql, err := builder.Insert().Into("table1").Select().From("table2").ToBoundSQL()
// INSERT INTO table1 (a, b) SELECT b, c FROM table2
sql, err = builder.Insert("a, b").Into("table1").Select("b, c").From("table2").ToBoundSQL()

Select

// Simple Query
sql, args, err := Select("c, d").From("table1").Where(Eq{"a": 1}).ToSQL()
// With join
sql, args, err = Select("c, d").From("table1").LeftJoin("table2", Eq{"table1.id": 1}.And(Lt{"table2.id": 3})).
        RightJoin("table3", "table2.id = table3.tid").Where(Eq{"a": 1}).ToSQL()
// From sub query
sql, args, err := Select("sub.id").From(Select("c").From("table1").Where(Eq{"a": 1}), "sub").Where(Eq{"b": 1}).ToSQL()
// From union query
sql, args, err = Select("sub.id").From(
    Select("id").From("table1").Where(Eq{"a": 1}).Union("all", Select("id").From("table1").Where(Eq{"a": 2})),"sub").
    Where(Eq{"b": 1}).ToSQL()
// With order by
sql, args, err = Select("a", "b", "c").From("table1").Where(Eq{"f1": "v1", "f2": "v2"}).
        OrderBy("a ASC").ToSQL()
// With limit.
// Be careful! You should set up specific dialect for builder before performing a query with LIMIT
sql, args, err = Dialect(MYSQL).Select("a", "b", "c").From("table1").OrderBy("a ASC").
        Limit(5, 10).ToSQL()

Update

sql, args, err := Update(Eq{"a": 2}).From("table1").Where(Eq{"a": 1}).ToSQL()

Delete

sql, args, err := Delete(Eq{"a": 1}).From("table1").ToSQL()

Union

sql, args, err := Select("*").From("a").Where(Eq{"status": "1"}).
        Union("all", Select("*").From("a").Where(Eq{"status": "2"})).
        Union("distinct", Select("*").From("a").Where(Eq{"status": "3"})).
        Union("", Select("*").From("a").Where(Eq{"status": "4"})).
        ToSQL()

Conditions

• Eq is a redefine of a map, you can give one or more conditions to Eq

import . "xorm.io/builder"
sql, args, _ := ToSQL(Eq{"a":1})
// a=? [1]
sql, args, _ := ToSQL(Eq{"b":"c"}.And(Eq{"c": 0}))
// b=? AND c=? ["c", 0]
sql, args, _ := ToSQL(Eq{"b":"c", "c":0})
// b=? AND c=? ["c", 0]
sql, args, _ := ToSQL(Eq{"b":"c"}.Or(Eq{"b":"d"}))
// b=? OR b=? ["c", "d"]
sql, args, _ := ToSQL(Eq{"b": []string{"c", "d"}})
// b IN (?,?) ["c", "d"]
sql, args, _ := ToSQL(Eq{"b": 1, "c":[]int{2, 3}})
// b=? AND c IN (?,?) [1, 2, 3]

• Neq is the same to Eq

import . "xorm.io/builder"
sql, args, _ := ToSQL(Neq{"a":1})
// a<>? [1]
sql, args, _ := ToSQL(Neq{"b":"c"}.And(Neq{"c": 0}))
// b<>? AND c<>? ["c", 0]
sql, args, _ := ToSQL(Neq{"b":"c", "c":0})
// b<>? AND c<>? ["c", 0]
sql, args, _ := ToSQL(Neq{"b":"c"}.Or(Neq{"b":"d"}))
// b<>? OR b<>? ["c", "d"]
sql, args, _ := ToSQL(Neq{"b": []string{"c", "d"}})
// b NOT IN (?,?) ["c", "d"]
sql, args, _ := ToSQL(Neq{"b": 1, "c":[]int{2, 3}})
// b<>? AND c NOT IN (?,?) [1, 2, 3]

• Gt, Gte, Lt, Lte

import . "xorm.io/builder"
sql, args, _ := ToSQL(Gt{"a", 1}.And(Gte{"b", 2}))
// a>? AND b>=? [1, 2]
sql, args, _ := ToSQL(Lt{"a", 1}.Or(Lte{"b", 2}))
// a<? OR b<=? [1, 2]

• Like

import . "xorm.io/builder"
sql, args, _ := ToSQL(Like{"a", "c"})
// a LIKE ? [%c%]

• Expr you can customerize your sql with Expr

import . "xorm.io/builder"
sql, args, _ := ToSQL(Expr("a = ? ", 1))
// a = ? [1]
sql, args, _ := ToSQL(Eq{"a": Expr("select id from table where c = ?", 1)})
// a=(select id from table where c = ?) [1]

• In and NotIn

import . "xorm.io/builder"
sql, args, _ := ToSQL(In("a", 1, 2, 3))
// a IN (?,?,?) [1,2,3]
sql, args, _ := ToSQL(In("a", []int{1, 2, 3}))
// a IN (?,?,?) [1,2,3]
sql, args, _ := ToSQL(NotIn("a", Expr("select id from b where c = ?", 1))))
// a NOT IN (select id from b where c = ?) [1]

• Exists and NotExists

import . "xorm.io/builder"
sql, args, _ := ToSQL(Exists(Select("a").From("table")))
// EXISTS (SELECT a FROM table)
sql, args, _ := ToSQL(NotExists(Select("a").From("table")))
// NOT EXISTS (SELECT a FROM table)

• IsNull and NotNull

import . "xorm.io/builder"
sql, args, _ := ToSQL(IsNull{"a"})
// a IS NULL []
sql, args, _ := ToSQL(NotNull{"b"})
    // b IS NOT NULL []

• And(conds ...Cond), And can connect one or more conditions via And

import . "xorm.io/builder"
sql, args, _ := ToSQL(And(Eq{"a":1}, Like{"b", "c"}, Neq{"d", 2}))
// a=? AND b LIKE ? AND d<>? [1, %c%, 2]

• Or(conds ...Cond), Or can connect one or more conditions via Or

import . "xorm.io/builder"
sql, args, _ := ToSQL(Or(Eq{"a":1}, Like{"b", "c"}, Neq{"d", 2}))
// a=? OR b LIKE ? OR d<>? [1, %c%, 2]
sql, args, _ := ToSQL(Or(Eq{"a":1}, And(Like{"b", "c"}, Neq{"d", 2})))
// a=? OR (b LIKE ? AND d<>?) [1, %c%, 2]

• Between

import . "xorm.io/builder"
sql, args, _ := ToSQL(Between{"a", 1, 2})
// a BETWEEN 1 AND 2

• Define yourself conditions

Since Cond is an interface.

type Cond interface {
    WriteTo(Writer) error
    And(...Cond) Cond
    Or(...Cond) Cond
    IsValid() bool
}

You can define yourself conditions and compose with other Cond.