您好,我正在尝试编写一个脚本来更新从文件中读取的行,到目前为止,除了最后提到的以下行之外,一切都工作正常
这是我的脚本:
#!/bin/bash
#INITIALIZE PATHS
DB_PATH=${1}
DATA_PATH="$DB_PATH/data/"
METADATA_PATH="$DB_PATH/metadata"
#LOAD THE META DB FILE AND READ DATABASE NAME IN DB_NAME
#READ ALSO COLUMNS IN AN ARRAY CALLED TABLE_NAMES
METADATA_LOAD=$(<"$METADATA_PATH/DB")
IFS=$'+'
read -a NAMES <<< "$METADATA_LOAD"
#PROMPET FOR TABLE TO UPDATE
echo ""
echo ""
echo ""
echo "You Currently Working with Database ${NAMES[0]}"
echo ""
echo "You Have The Following Tables to Choose From :"
IFS=' '
for token in ${NAMES[@]:1}
do
echo " $token"
done
echo ""
echo ""
echo ""
echo "Please Write The Name Of The Table You Want To Update :"
read CURRENT_TABLE
#Form META DATA TABLE FILE PATH
TABLE_DATA_PATH="$DB_PATH/data/$CURRENT_TABLE"
TABLE_METADATA_PATH="$DB_PATH/metadata/$CURRENT_TABLE"
#PROMPET WHICH COLUMN IS NEEDED TO CHECK FOR EQUALITY
echo ""
echo ""
echo ""
echo "The Table You Selected Have The Following Columns"
i=0
TABLE_METADATA=$(<"$TABLE_METADATA_PATH")
IFS='+'
read -a CURRENT_TABLE_META <<< "$TABLE_METADATA"
IFS=' '
for token in ${CURRENT_TABLE_META[@]:1}
do
i=$(($i+1))
echo $i $token
done
echo "Please Enter The Number Column to Check For Equality"
read TEST_COLUMN_NUM
echo ""
echo ""
echo "Please Enter The Column Value to Check For Equality"
read TEST_COLUMN_VAL
echo "Please Enter The Column Number to Modify"
read MODIFY_COLUMN_NUM
echo "Please Enter The New Column Value"
read MODIFY_COLUMN_VAL
#Form DATA TABLE FILE PATH
TABLE_DATA=$(<"$TABLE_DATA_PATH")
IFS=' '
read -a ROWS_ARRAY <<< "$TABLE_DATA"
for CURRENT_ROW_INDEX in ${!ROWS_ARRAY[@]}
do
IFS=':'
read -a COLUMNS_ARRAY <<< "${ROWS_ARRAY[CURRENT_ROW_INDEX]}"
for CURRENT_COL_INDEX in ${!COLUMNS_ARRAY[@]}
do
if [[ ${COLUMNS_ARRAY[$CURRENT_COL_INDEX]} == $TEST_COLUMN_VAL && $CURRENT_COL_INDEX -eq $(($TEST_COLUMN_NUM-1)) ]]
then
IFS=' '
COLUMNS_ARRAY[$MODIFY_COLUMN_NUM] = "ABC"
fi
done
done
我还没有完成脚本,但我在该行出现错误:
COLUMNS_ARRAY[$MODIFY_COLUMN_NUM] = "ABC"
它给了我错误
./更新:第 91 行:COLUMNS_ARRAY[3]:找不到命令
我想分配给给定索引处的数组替换旧值,请帮助我了解错误原因以及如何解决它
答案1
与 shell 中的常规变量分配相同,不要在=
.
给定,这是对中i=123
索引的赋值:123
array
array[$i]="abc"
这会尝试运行一个名为的命令array[123]
(或者如果找到与 glob 模式匹配的文件名,则任何结果):
array[$i] = "abc"
另外,每次使用${array[@]}
, 时,无论是否带有!
or :n:m
,您都可能需要在其周围加上引号。如果没有引号,数组值会受到分词的影响,而有引号则不会。
你有,例如for token in ${NAMES[@]:1}
和for .. in ${!ROWS_ARRAY[@]}