2020-02-02 09:40:44 +03:00
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package clause
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2020-02-07 18:45:35 +03:00
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import "strconv"
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2020-02-02 09:40:44 +03:00
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// Limit limit clause
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type Limit struct {
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2020-02-07 18:45:35 +03:00
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Limit int
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Offset int
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}
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// Name where clause name
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func (limit Limit) Name() string {
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return "LIMIT"
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}
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// Build build where clause
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func (limit Limit) Build(builder Builder) {
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if limit.Limit > 0 {
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2020-03-09 12:07:00 +03:00
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builder.WriteString("LIMIT ")
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builder.WriteString(strconv.Itoa(limit.Limit))
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2020-02-07 18:45:35 +03:00
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2020-03-07 08:43:20 +03:00
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if limit.Offset > 0 {
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2020-03-09 12:07:00 +03:00
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builder.WriteString(" OFFSET ")
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builder.WriteString(strconv.Itoa(limit.Offset))
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2020-03-07 08:43:20 +03:00
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}
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2020-02-07 18:45:35 +03:00
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}
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}
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// MergeClause merge order by clauses
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func (limit Limit) MergeClause(clause *Clause) {
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clause.Name = ""
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if v, ok := clause.Expression.(Limit); ok {
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if limit.Limit == 0 && v.Limit > 0 {
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limit.Limit = v.Limit
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2020-03-04 18:56:42 +03:00
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} else if limit.Limit < 0 {
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limit.Limit = 0
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2020-02-07 18:45:35 +03:00
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}
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if limit.Offset == 0 && v.Offset > 0 {
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limit.Offset = v.Offset
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2020-03-04 18:56:42 +03:00
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} else if limit.Offset < 0 {
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limit.Offset = 0
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2020-02-07 18:45:35 +03:00
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}
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}
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clause.Expression = limit
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2020-02-02 09:40:44 +03:00
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}
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