init

mysql_print.lua

@@ -0,0 +1,144 @@
+--mysql table pretty printing
+
+local function ellipsis(s,n)
+	return #s > n and (s:sub(1,n-3) .. '...') or s
+end
+
+local align = {}
+
+function align.left(s,n)
+	s = s..(' '):rep(n - #s)
+	return ellipsis(s,n)
+end
+
+function align.right(s,n)
+	s = (' '):rep(n - #s)..s
+	return ellipsis(s,n)
+end
+
+function align.center(s,n)
+	local total = n - #s
+	local left = math.floor(total / 2)
+	local right = math.ceil(total / 2)
+	s = (' '):rep(left)..s..(' '):rep(right)
+	return ellipsis(s,n)
+end
+
+local function fit(s,n,al)
+	return align[al or 'left'](s,n)
+end
+
+local function print_table(fields, rows, aligns, minsize, print)
+	print = print or _G.print
+	minsize = minsize or math.huge
+	local max_sizes = {}
+	for i=1,#rows do
+		for j=1,#fields do
+			max_sizes[j] = math.min(minsize, math.max(max_sizes[j] or 0, #rows[i][j]))
+		end
+	end
+
+	local totalsize = 0
+	for j=1,#fields do
+		max_sizes[j] = math.max(max_sizes[j] or 0, #fields[j])
+		totalsize = totalsize + max_sizes[j] + 3
+	end
+
+	print()
+	local s, ps = '', ''
+	for j=1,#fields do
+		s = s .. fit(fields[j], max_sizes[j], 'center') .. ' | '
+		ps = ps .. ('-'):rep(max_sizes[j]) .. ' + '
+	end
+	print(s)
+	print(ps)
+
+	for i=1,#rows do
+		local s = ''
+		for j=1,#fields do
+			local val = rows[i][j]
+			s = s .. fit(val, max_sizes[j], aligns and aligns[j]) .. ' | '
+		end
+		print(s)
+	end
+	print()
+end
+
+local function invert_table(fields, rows, minsize)
+	local ft, rt = {'field'}, {}
+	for i=1,#rows do
+		ft[i+1] = tostring(i)
+	end
+	for j=1,#fields do
+		local row = {fields[j]}
+		for i=1,#rows do
+			row[i+1] = rows[i][j]
+		end
+		rt[j] = row
+	end
+	return ft, rt
+end
+
+local function format_cell(v)
+	if v == nil then
+		return 'NULL'
+	else
+		return tostring(v)
+	end
+end
+
+local function cell_align(current_align, cell_value)
+	if current_align == 'left' then return 'left' end
+	if type(cell_value) == 'number' or type(cell_value) == 'cdata' then return 'right' end
+	return 'left'
+end
+
+local function print_result(res, minsize, print)
+	local fields = {}
+	for i,field in res:fields() do
+		fields[i] = field.name
+	end
+	local rows = {}
+	local aligns = {} --deduced from values
+	for i,row in res:rows'n' do
+		local t = {}
+		for j=1,#fields do
+			t[j] = format_cell(row[j])
+			aligns[j] = cell_align(aligns[j], row[j])
+		end
+		rows[i] = t
+	end
+	print_table(fields, rows, aligns, minsize, print)
+end
+
+local function print_statement(stmt, minsize, print)
+	local res = stmt:bind_result()
+	local fields = {}
+	for i,field in stmt:fields() do
+		fields[i] = field.name
+	end
+	local rows = {}
+	local aligns = {}
+	while stmt:fetch() do
+		local row = {}
+		for i=1,#fields do
+			local v = res:get(i)
+			row[i] = format_cell(v)
+			aligns[i] = cell_align(aligns[i], v)
+		end
+		rows[#rows+1] = row
+	end
+	stmt:close()
+	print_table(fields, rows, aligns, minsize, print)
+end
+
+if not ... then require'mysql_test' end
+
+return {
+	fit = fit,
+	format_cell = format_cell,
+	table = print_table,
+	result = print_result,
+	statement = print_statement,
+}
+